{"id":7322,"date":"2026-06-17T03:30:51","date_gmt":"2026-06-17T03:30:51","guid":{"rendered":"http:\/\/australianholden.com\/?p=7322"},"modified":"2026-06-21T12:41:07","modified_gmt":"2026-06-21T12:41:07","slug":"hq-hj-hx-hz-and-wb-radiator-upgrade-guide","status":"publish","type":"post","link":"https:\/\/australianholden.com\/index.php\/2026\/06\/17\/hq-hj-hx-hz-and-wb-radiator-upgrade-guide\/","title":{"rendered":"HQ, HJ, HX, HZ and WB Radiator Upgrade Guide"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">The HQ, HJ, HX, HZ and WB Holden range remains one of the most popular classic Holden platforms in Australia. Whether you&#8217;re driving a Kingswood, Premier, Sandman, One Tonner, Statesman or WB ute, chances are you&#8217;ve either experienced cooling system problems or know someone who has.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">When these cars rolled off the production line in the 1970s, their factory cooling systems were more than adequate for the conditions of the day. Traffic was lighter, fuel quality was different, and most vehicles were not expected to spend hours idling in congested urban traffic with air conditioning running.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Fast forward several decades and many HQ-WB Holdens now run larger engines, higher compression ratios, aftermarket camshafts, air conditioning systems and modern driving schedules. Add ageing radiators and decades of internal corrosion and it becomes clear why radiator upgrades are one of the most popular modifications among Holden enthusiasts.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Why Upgrade the Factory Radiator?<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">The original brass and copper radiators fitted to HQ-WB Holdens were excellent for their era, but time eventually catches up with everything.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Common Problems<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Internal blockage<\/li>\n\n\n\n<li>Corroded cores<\/li>\n\n\n\n<li>Reduced cooling efficiency<\/li>\n\n\n\n<li>Damaged fins<\/li>\n\n\n\n<li>Repeated overheating<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Many original radiators are now over 40 years old and operating well beyond their intended lifespan.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Even professionally re-cored factory radiators can struggle when paired with modified engines or modern traffic conditions.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Signs Your Holden Needs a Radiator Upgrade<\/h1>\n\n\n\n<h3 class=\"wp-block-heading\">Temperature Gauge Runs Hot<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">If your gauge consistently sits higher than normal, radiator efficiency may be compromised.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Overheats in Traffic<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A common symptom of inadequate cooling capacity.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Coolant Loss<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Small leaks often develop around tanks and core joints.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Rusty Coolant<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Internal corrosion reduces heat transfer and coolant flow.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Frequent Cooling System Repairs<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Repeated repairs often indicate the radiator itself has reached the end of its useful life.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Aluminium vs Brass Radiators<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">One of the biggest decisions is whether to retain a traditional brass radiator or upgrade to aluminium.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Brass and Copper Radiators<\/h1>\n\n\n\n<h3 class=\"wp-block-heading\">Advantages<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Original appearance<\/li>\n\n\n\n<li>Easy to repair<\/li>\n\n\n\n<li>Factory-correct restoration option<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Disadvantages<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Heavier<\/li>\n\n\n\n<li>Less efficient heat transfer<\/li>\n\n\n\n<li>More susceptible to age-related deterioration<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Ideal for concours restorations and factory-correct vehicles.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Aluminium Radiators<\/h1>\n\n\n\n<h3 class=\"wp-block-heading\">Advantages<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Better cooling performance<\/li>\n\n\n\n<li>Lighter weight<\/li>\n\n\n\n<li>Improved durability<\/li>\n\n\n\n<li>Excellent availability<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Disadvantages<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Less original appearance<\/li>\n\n\n\n<li>Higher initial purchase price<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">For most drivers, aluminium represents the best cooling upgrade available.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Best Overall Radiator Upgrade<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">Recommended Product: Alloy Works Aluminium Radiator<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Benefits<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>High-efficiency aluminium construction<\/li>\n\n\n\n<li>Larger cooling capacity<\/li>\n\n\n\n<li>Direct-fit options available<\/li>\n\n\n\n<li>Excellent value for money<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Best For<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Holden 202 engines<\/li>\n\n\n\n<li>Holden 253 V8s<\/li>\n\n\n\n<li>Holden 308 V8s<\/li>\n\n\n\n<li>Mild performance builds<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">This is one of the most commonly used upgrades among Australian Holden enthusiasts.<\/p>\n\n\n<div id=\"fu_ebay_0\"><!-- Presentation: cols = 4, rows = 2, slideshow = Manual, slides = 3, slideId = 0 --><div class=\"fu_ebay_results_container \">\n<h5 class=\"fu_ebay_results_title\" style=\"display: block !important;\">\n<a name=\"fu_slidetop_0\"><\/a><a href=\"https:\/\/www.ebay.com.au\/?mkcid=1&#038;mkrid=705-53470-19255-0&#038;siteid=15&#038;campid=5339152561&#038;customid=5339151688&#038;toolid=10049&#038;mkevt=1\" class=\"fu_ebay\" style=\"display:inline !important;\" rel=\"nofollow\" target=\"_blank\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/australianholden.com\/wp-content\/plugins\/fast-ebay-listings\/US\/Right_Now_108x45.gif?resize=108%2C45&#038;ssl=1\" style=\"border:0;display:block !important;\" width=\"108\" height=\"45\" alt=\"Right Now on eBay\"\/><\/a>&nbsp;HQ HJ HX HZ WB radiator <\/h5>\nLoading&#8230;<\/div>\n<\/div>\n<script>\n<!--\nvar content_fu_ebay_0 = null;\nvar waitForDepends_fu_ebay_0 = setInterval(function () {\n  if (typeof jQuery !== \"undefined\") {\n  if (window.fu_is_bot_useragent !== undefined) {\n    clearInterval(waitForDepends_fu_ebay_0);\n    if (typeof jQuery.ajax == \"undefined\") {\n      console.log(\"Fast eBay Listings: jQuery.ajax missing. Are you using jQuery.Slim that doesn't include ajax? \");\n      return;\n    }\n    if (fu_is_bot_useragent) return;\n    content_fu_ebay_0 = jQuery(\"#fu_ebay_0\");\n    jQuery(document).ready(jQuery.ajax({\n      type : \"post\",\n      url : \"https:\/\/australianholden.com\/wp-admin\/admin-ajax.php\",\n      data : {\n        action : \"fu_ebay_load_search\",\nfuDisableAPICache : 0,\nfuTraceLogging : 0,\nebay_country : \"AU\",\nfu_ebay_customId : \"\",\nfu_ebay_widget : 0,\nfu_ebay_picwidth : 225,\nfu_ebay_arrangement : 0,\nfu_ebay_title : \"HQ HJ HX HZ WB radiator \",\nfu_ebay_query : \"HQ HJ HX HZ WB radiator \",\nfu_ebay_searchInDesc : 0,\nfu_ebay_searchLocation : \"Internationally\",\nfu_ebay_pickupPostcode : \"\",\nfu_ebay_pickupRadius : 0,\nfu_ebay_sort : \"BestMatch\",\nfu_ebay_categoryIds : \"6030\",\nfu_ebay_sellers : \"\",\nfu_ebay_sellerType : \"\",\nfu_ebay_buyingOptions : \"\",\nfu_ebay_conditionOptions : \"\",\nfu_ebay_minPrice : 0,\nfu_ebay_maxPrice : 0,\nfu_ebay_minBids : 0,\nfu_ebay_maxBids : 0,\nfu_cols : 4,\nfu_rows : 2,\nfu_slideshow : \"Manual\",\nfu_slides : 3,\nfu_slideId : 0,\n\n      },\n      success : function( response ) {\n        content_fu_ebay_0.html( response );\n      },\n      error: function(e) {\n        console.log(\"Fast eBay Listings: deferred loading error: \" + e);\n      }\n    }));\n  }}\n}, 10);\n\/\/-->\n<\/script>\n\n\n\n<h1 class=\"wp-block-heading\">Best Premium Radiator Upgrade<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">Recommended Product: PWR Performance Radiator<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Benefits<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Exceptional build quality<\/li>\n\n\n\n<li>Australian-made<\/li>\n\n\n\n<li>Outstanding cooling efficiency<\/li>\n\n\n\n<li>Suitable for high-performance applications<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Best For<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Modified V8s<\/li>\n\n\n\n<li>High-horsepower builds<\/li>\n\n\n\n<li>Towing applications<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">PWR products are widely regarded as among the best cooling solutions available.<\/p>\n\n\n<div id=\"fu_ebay_1\"><!-- Presentation: cols = 4, rows = 2, slideshow = Manual, slides = 3, slideId = 1 --><div class=\"fu_ebay_results_container \">\n<h5 class=\"fu_ebay_results_title\" style=\"display: block !important;\">\n<a name=\"fu_slidetop_1\"><\/a><a href=\"https:\/\/www.ebay.com.au\/?mkcid=1&#038;mkrid=705-53470-19255-0&#038;siteid=15&#038;campid=5339152561&#038;customid=5339151688&#038;toolid=10049&#038;mkevt=1\" class=\"fu_ebay\" style=\"display:inline !important;\" rel=\"nofollow\" target=\"_blank\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/australianholden.com\/wp-content\/plugins\/fast-ebay-listings\/US\/Right_Now_108x45.gif?resize=108%2C45&#038;ssl=1\" style=\"border:0;display:block !important;\" width=\"108\" height=\"45\" alt=\"Right Now on eBay\"\/><\/a>&nbsp;PWR Holden radiator <\/h5>\nLoading&#8230;<\/div>\n<\/div>\n<script>\n<!--\nvar content_fu_ebay_1 = null;\nvar waitForDepends_fu_ebay_1 = setInterval(function () {\n  if (typeof jQuery !== \"undefined\") {\n  if (window.fu_is_bot_useragent !== undefined) {\n    clearInterval(waitForDepends_fu_ebay_1);\n    if (typeof jQuery.ajax == \"undefined\") {\n      console.log(\"Fast eBay Listings: jQuery.ajax missing. Are you using jQuery.Slim that doesn't include ajax? \");\n      return;\n    }\n    if (fu_is_bot_useragent) return;\n    content_fu_ebay_1 = jQuery(\"#fu_ebay_1\");\n    jQuery(document).ready(jQuery.ajax({\n      type : \"post\",\n      url : \"https:\/\/australianholden.com\/wp-admin\/admin-ajax.php\",\n      data : {\n        action : \"fu_ebay_load_search\",\nfuDisableAPICache : 0,\nfuTraceLogging : 0,\nebay_country : \"AU\",\nfu_ebay_customId : \"\",\nfu_ebay_widget : 0,\nfu_ebay_picwidth : 225,\nfu_ebay_arrangement : 0,\nfu_ebay_title : \"PWR Holden radiator \",\nfu_ebay_query : \"PWR Holden radiator \",\nfu_ebay_searchInDesc : 0,\nfu_ebay_searchLocation : \"Internationally\",\nfu_ebay_pickupPostcode : \"\",\nfu_ebay_pickupRadius : 0,\nfu_ebay_sort : \"BestMatch\",\nfu_ebay_categoryIds : \"6030\",\nfu_ebay_sellers : \"\",\nfu_ebay_sellerType : \"\",\nfu_ebay_buyingOptions : \"\",\nfu_ebay_conditionOptions : \"\",\nfu_ebay_minPrice : 0,\nfu_ebay_maxPrice : 0,\nfu_ebay_minBids : 0,\nfu_ebay_maxBids : 0,\nfu_cols : 4,\nfu_rows : 2,\nfu_slideshow : \"Manual\",\nfu_slides : 3,\nfu_slideId : 1,\n\n      },\n      success : function( response ) {\n        content_fu_ebay_1.html( response );\n      },\n      error: function(e) {\n        console.log(\"Fast eBay Listings: deferred loading error: \" + e);\n      }\n    }));\n  }}\n}, 10);\n\/\/-->\n<\/script>\n\n\n\n<h1 class=\"wp-block-heading\">Choosing the Correct Radiator Size<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Not every Holden requires a massive racing radiator.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Holden 202 Six-Cylinder<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A quality two-row aluminium radiator is usually sufficient.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Suitable For<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Stock engines<\/li>\n\n\n\n<li>Mild modifications<\/li>\n\n\n\n<li>Weekend cruisers<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Holden 253 V8<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A larger two-row or three-row aluminium radiator is recommended.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Suitable For<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Stock V8s<\/li>\n\n\n\n<li>Mild performance upgrades<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Holden 308 V8<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A high-capacity aluminium radiator is strongly recommended.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Suitable For<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Performance builds<\/li>\n\n\n\n<li>Air-conditioned vehicles<\/li>\n\n\n\n<li>Summer driving<\/li>\n<\/ul>\n\n\n\n<h1 class=\"wp-block-heading\">Fan Upgrades<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">A radiator upgrade alone may not solve all cooling problems.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Proper airflow is equally important.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Best Electric Fan Upgrade<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">Recommended Product: Davies Craig Thermatic Fan Kit<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Benefits<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Improved airflow at idle<\/li>\n\n\n\n<li>Reduced engine load<\/li>\n\n\n\n<li>Adjustable temperature control<\/li>\n\n\n\n<li>Increased cooling efficiency<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Best For<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>City driving<\/li>\n\n\n\n<li>Modified engines<\/li>\n\n\n\n<li>Air-conditioned vehicles<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Electric fans are particularly effective for cars that spend significant time in traffic.<\/p>\n\n\n<div id=\"fu_ebay_2\"><!-- Presentation: cols = 4, rows = 2, slideshow = Manual, slides = 3, slideId = 2 --><div class=\"fu_ebay_results_container \">\n<h5 class=\"fu_ebay_results_title\" style=\"display: block !important;\">\n<a name=\"fu_slidetop_2\"><\/a><a href=\"https:\/\/www.ebay.com.au\/?mkcid=1&#038;mkrid=705-53470-19255-0&#038;siteid=15&#038;campid=5339152561&#038;customid=5339151688&#038;toolid=10049&#038;mkevt=1\" class=\"fu_ebay\" style=\"display:inline !important;\" rel=\"nofollow\" target=\"_blank\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/australianholden.com\/wp-content\/plugins\/fast-ebay-listings\/US\/Right_Now_108x45.gif?resize=108%2C45&#038;ssl=1\" style=\"border:0;display:block !important;\" width=\"108\" height=\"45\" alt=\"Right Now on eBay\"\/><\/a>&nbsp;Davies Craig thermatic fan kit<\/h5>\nLoading&#8230;<\/div>\n<\/div>\n<script>\n<!--\nvar content_fu_ebay_2 = null;\nvar waitForDepends_fu_ebay_2 = setInterval(function () {\n  if (typeof jQuery !== \"undefined\") {\n  if (window.fu_is_bot_useragent !== undefined) {\n    clearInterval(waitForDepends_fu_ebay_2);\n    if (typeof jQuery.ajax == \"undefined\") {\n      console.log(\"Fast eBay Listings: jQuery.ajax missing. Are you using jQuery.Slim that doesn't include ajax? \");\n      return;\n    }\n    if (fu_is_bot_useragent) return;\n    content_fu_ebay_2 = jQuery(\"#fu_ebay_2\");\n    jQuery(document).ready(jQuery.ajax({\n      type : \"post\",\n      url : \"https:\/\/australianholden.com\/wp-admin\/admin-ajax.php\",\n      data : {\n        action : \"fu_ebay_load_search\",\nfuDisableAPICache : 0,\nfuTraceLogging : 0,\nebay_country : \"AU\",\nfu_ebay_customId : \"\",\nfu_ebay_widget : 0,\nfu_ebay_picwidth : 225,\nfu_ebay_arrangement : 0,\nfu_ebay_title : \"Davies Craig thermatic fan kit\",\nfu_ebay_query : \"Davies Craig thermatic fan kit\",\nfu_ebay_searchInDesc : 0,\nfu_ebay_searchLocation : \"Internationally\",\nfu_ebay_pickupPostcode : \"\",\nfu_ebay_pickupRadius : 0,\nfu_ebay_sort : \"BestMatch\",\nfu_ebay_categoryIds : \"6030\",\nfu_ebay_sellers : \"\",\nfu_ebay_sellerType : \"\",\nfu_ebay_buyingOptions : \"\",\nfu_ebay_conditionOptions : \"\",\nfu_ebay_minPrice : 0,\nfu_ebay_maxPrice : 0,\nfu_ebay_minBids : 0,\nfu_ebay_maxBids : 0,\nfu_cols : 4,\nfu_rows : 2,\nfu_slideshow : \"Manual\",\nfu_slides : 3,\nfu_slideId : 2,\n\n      },\n      success : function( response ) {\n        content_fu_ebay_2.html( response );\n      },\n      error: function(e) {\n        console.log(\"Fast eBay Listings: deferred loading error: \" + e);\n      }\n    }));\n  }}\n}, 10);\n\/\/-->\n<\/script>\n\n\n\n<h1 class=\"wp-block-heading\">Fan Shrouds Matter<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Many HQ-WB Holdens are missing their factory fan shrouds.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Why It Matters<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The shroud directs airflow through the entire radiator core.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Without a shroud:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Airflow decreases<\/li>\n\n\n\n<li>Cooling efficiency drops<\/li>\n\n\n\n<li>Overheating becomes more likely<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Always retain or replace the shroud when upgrading cooling components.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Water Pump Considerations<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">A radiator upgrade should be paired with a healthy water pump.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Best Water Pump Upgrade<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">Recommended Product: GMB Water Pump<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Benefits<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>OEM-quality performance<\/li>\n\n\n\n<li>Excellent reliability<\/li>\n\n\n\n<li>Strong coolant circulation<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Best For<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Holden sixes<\/li>\n\n\n\n<li>Holden V8s<\/li>\n\n\n\n<li>Complete cooling system rebuilds<\/li>\n<\/ul>\n\n\n<div id=\"fu_ebay_3\"><!-- Presentation: cols = 4, rows = 2, slideshow = Manual, slides = 3, slideId = 3 --><div class=\"fu_ebay_results_container \">\n<h5 class=\"fu_ebay_results_title\" style=\"display: block !important;\">\n<a name=\"fu_slidetop_3\"><\/a><a href=\"https:\/\/www.ebay.com.au\/?mkcid=1&#038;mkrid=705-53470-19255-0&#038;siteid=15&#038;campid=5339152561&#038;customid=5339151688&#038;toolid=10049&#038;mkevt=1\" class=\"fu_ebay\" style=\"display:inline !important;\" rel=\"nofollow\" target=\"_blank\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/australianholden.com\/wp-content\/plugins\/fast-ebay-listings\/US\/Right_Now_108x45.gif?resize=108%2C45&#038;ssl=1\" style=\"border:0;display:block !important;\" width=\"108\" height=\"45\" alt=\"Right Now on eBay\"\/><\/a>&nbsp;GMB Water Pump<\/h5>\nLoading&#8230;<\/div>\n<\/div>\n<script>\n<!--\nvar content_fu_ebay_3 = null;\nvar waitForDepends_fu_ebay_3 = setInterval(function () {\n  if (typeof jQuery !== \"undefined\") {\n  if (window.fu_is_bot_useragent !== undefined) {\n    clearInterval(waitForDepends_fu_ebay_3);\n    if (typeof jQuery.ajax == \"undefined\") {\n      console.log(\"Fast eBay Listings: jQuery.ajax missing. Are you using jQuery.Slim that doesn't include ajax? \");\n      return;\n    }\n    if (fu_is_bot_useragent) return;\n    content_fu_ebay_3 = jQuery(\"#fu_ebay_3\");\n    jQuery(document).ready(jQuery.ajax({\n      type : \"post\",\n      url : \"https:\/\/australianholden.com\/wp-admin\/admin-ajax.php\",\n      data : {\n        action : \"fu_ebay_load_search\",\nfuDisableAPICache : 0,\nfuTraceLogging : 0,\nebay_country : \"AU\",\nfu_ebay_customId : \"\",\nfu_ebay_widget : 0,\nfu_ebay_picwidth : 225,\nfu_ebay_arrangement : 0,\nfu_ebay_title : \"GMB Water Pump\",\nfu_ebay_query : \"GMB Water Pump Holden\",\nfu_ebay_searchInDesc : 0,\nfu_ebay_searchLocation : \"Internationally\",\nfu_ebay_pickupPostcode : \"\",\nfu_ebay_pickupRadius : 0,\nfu_ebay_sort : \"BestMatch\",\nfu_ebay_categoryIds : \"6030\",\nfu_ebay_sellers : \"\",\nfu_ebay_sellerType : \"\",\nfu_ebay_buyingOptions : \"\",\nfu_ebay_conditionOptions : \"\",\nfu_ebay_minPrice : 0,\nfu_ebay_maxPrice : 0,\nfu_ebay_minBids : 0,\nfu_ebay_maxBids : 0,\nfu_cols : 4,\nfu_rows : 2,\nfu_slideshow : \"Manual\",\nfu_slides : 3,\nfu_slideId : 3,\n\n      },\n      success : function( response ) {\n        content_fu_ebay_3.html( response );\n      },\n      error: function(e) {\n        console.log(\"Fast eBay Listings: deferred loading error: \" + e);\n      }\n    }));\n  }}\n}, 10);\n\/\/-->\n<\/script>\n\n\n\n<h1 class=\"wp-block-heading\">Thermostat Selection<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">A quality thermostat is critical for proper temperature control.<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">Best Thermostat Upgrade<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">Recommended Product: Tridon High Flow Thermostat<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Benefits<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Consistent operating temperatures<\/li>\n\n\n\n<li>Reliable opening characteristics<\/li>\n\n\n\n<li>Improved coolant flow<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Best For<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Standard engines<\/li>\n\n\n\n<li>Modified engines<\/li>\n\n\n\n<li>Performance applications<\/li>\n<\/ul>\n\n\n<div id=\"fu_ebay_4\"><!-- Presentation: cols = 4, rows = 2, slideshow = Manual, slides = 3, slideId = 4 --><div class=\"fu_ebay_results_container \">\n<h5 class=\"fu_ebay_results_title\" style=\"display: block !important;\">\n<a name=\"fu_slidetop_4\"><\/a><a href=\"https:\/\/www.ebay.com.au\/?mkcid=1&#038;mkrid=705-53470-19255-0&#038;siteid=15&#038;campid=5339152561&#038;customid=5339151688&#038;toolid=10049&#038;mkevt=1\" class=\"fu_ebay\" style=\"display:inline !important;\" rel=\"nofollow\" target=\"_blank\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/australianholden.com\/wp-content\/plugins\/fast-ebay-listings\/US\/Right_Now_108x45.gif?resize=108%2C45&#038;ssl=1\" style=\"border:0;display:block !important;\" width=\"108\" height=\"45\" alt=\"Right Now on eBay\"\/><\/a>&nbsp;Tridon<\/h5>\nLoading&#8230;<\/div>\n<\/div>\n<script>\n<!--\nvar content_fu_ebay_4 = null;\nvar waitForDepends_fu_ebay_4 = setInterval(function () {\n  if (typeof jQuery !== \"undefined\") {\n  if (window.fu_is_bot_useragent !== undefined) {\n    clearInterval(waitForDepends_fu_ebay_4);\n    if (typeof jQuery.ajax == \"undefined\") {\n      console.log(\"Fast eBay Listings: jQuery.ajax missing. Are you using jQuery.Slim that doesn't include ajax? \");\n      return;\n    }\n    if (fu_is_bot_useragent) return;\n    content_fu_ebay_4 = jQuery(\"#fu_ebay_4\");\n    jQuery(document).ready(jQuery.ajax({\n      type : \"post\",\n      url : \"https:\/\/australianholden.com\/wp-admin\/admin-ajax.php\",\n      data : {\n        action : \"fu_ebay_load_search\",\nfuDisableAPICache : 0,\nfuTraceLogging : 0,\nebay_country : \"AU\",\nfu_ebay_customId : \"\",\nfu_ebay_widget : 0,\nfu_ebay_picwidth : 225,\nfu_ebay_arrangement : 0,\nfu_ebay_title : \"Tridon\",\nfu_ebay_query : \"Tridon thermostat Holden\",\nfu_ebay_searchInDesc : 0,\nfu_ebay_searchLocation : \"Internationally\",\nfu_ebay_pickupPostcode : \"\",\nfu_ebay_pickupRadius : 0,\nfu_ebay_sort : \"BestMatch\",\nfu_ebay_categoryIds : \"6030\",\nfu_ebay_sellers : \"\",\nfu_ebay_sellerType : \"\",\nfu_ebay_buyingOptions : \"\",\nfu_ebay_conditionOptions : \"\",\nfu_ebay_minPrice : 0,\nfu_ebay_maxPrice : 0,\nfu_ebay_minBids : 0,\nfu_ebay_maxBids : 0,\nfu_cols : 4,\nfu_rows : 2,\nfu_slideshow : \"Manual\",\nfu_slides : 3,\nfu_slideId : 4,\n\n      },\n      success : function( response ) {\n        content_fu_ebay_4.html( response );\n      },\n      error: function(e) {\n        console.log(\"Fast eBay Listings: deferred loading error: \" + e);\n      }\n    }));\n  }}\n}, 10);\n\/\/-->\n<\/script>\n\n\n\n<h1 class=\"wp-block-heading\">Best Coolant for HQ-WB Holdens<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Coolant is often overlooked when upgrading the cooling system.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Recommended Product: Penrite Classic Car Coolant<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Benefits<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Corrosion protection<\/li>\n\n\n\n<li>Compatible with older metals<\/li>\n\n\n\n<li>Suitable for brass and aluminium radiators<\/li>\n\n\n\n<li>Long service life<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Best For<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Restored vehicles<\/li>\n\n\n\n<li>Daily drivers<\/li>\n\n\n\n<li>Performance builds<\/li>\n<\/ul>\n\n\n<div id=\"fu_ebay_5\"><!-- Presentation: cols = 4, rows = 2, slideshow = Manual, slides = 3, slideId = 5 --><div class=\"fu_ebay_results_container \">\n<h5 class=\"fu_ebay_results_title\" style=\"display: block !important;\">\n<a name=\"fu_slidetop_5\"><\/a><a href=\"https:\/\/www.ebay.com.au\/?mkcid=1&#038;mkrid=705-53470-19255-0&#038;siteid=15&#038;campid=5339152561&#038;customid=5339151688&#038;toolid=10049&#038;mkevt=1\" class=\"fu_ebay\" style=\"display:inline !important;\" rel=\"nofollow\" target=\"_blank\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/australianholden.com\/wp-content\/plugins\/fast-ebay-listings\/US\/Right_Now_108x45.gif?resize=108%2C45&#038;ssl=1\" style=\"border:0;display:block !important;\" width=\"108\" height=\"45\" alt=\"Right Now on eBay\"\/><\/a>&nbsp;Penrite Classic Car Coolant<\/h5>\nLoading&#8230;<\/div>\n<\/div>\n<script>\n<!--\nvar content_fu_ebay_5 = null;\nvar waitForDepends_fu_ebay_5 = setInterval(function () {\n  if (typeof jQuery !== \"undefined\") {\n  if (window.fu_is_bot_useragent !== undefined) {\n    clearInterval(waitForDepends_fu_ebay_5);\n    if (typeof jQuery.ajax == \"undefined\") {\n      console.log(\"Fast eBay Listings: jQuery.ajax missing. 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While they performed admirably when new, decades of corrosion, sediment buildup and component wear have reduced their effectiveness considerably.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A quality radiator upgrade is one of the best investments you can make in the reliability and longevity of your Holden. Combined with a healthy water pump, proper thermostat, effective fan setup and quality coolant, a modern cooling package can transform how these classic cars perform in Australian conditions.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Whether you&#8217;re maintaining a stock Kingswood or building a tough 308-powered street machine, upgrading the radiator is one modification you&#8217;ll appreciate every time the temperature gauge stays exactly where it should.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Related Articles<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><a href=\"https:\/\/australianholden.com\/index.php\/2026\/06\/17\/hq-hj-hx-hz-and-wb-holden-cooling-system-problems\/\" type=\"post\" id=\"7320\">HQ HJ HX HZ WB Holden Cooling System Problems<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/australianholden.com\/index.php\/2026\/06\/20\/holden-202-engine-issues-explained\/\" type=\"post\" id=\"7311\">Holden 202 Engine Issues Explained<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/australianholden.com\/index.php\/2026\/06\/16\/holden-253-308-v8-issues-explained\/\" type=\"post\" id=\"7340\">Holden 308 V8 Issues Explained<\/a><\/li>\n\n\n\n<li>Best Coolants for Classic Holdens<\/li>\n\n\n\n<li><a href=\"https:\/\/australianholden.com\/index.php\/2026\/06\/17\/how-to-inspect-a-hq-hj-hx-hz-or-wb-holden-before-buying\/\" type=\"post\" id=\"7318\">How to Inspect a HQ HJ HX HZ WB Holden Before Buying<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/australianholden.com\/index.php\/2026\/06\/17\/hq-hj-hx-hz-and-wb-holden-rust-problems\/\" type=\"post\" id=\"7316\">HQ HJ HX HZ WB Holden Rust Problems<\/a><\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>The HQ, HJ, HX, HZ and WB Holden range remains one of the most popular classic Holden platforms in Australia. Whether you&#8217;re driving a Kingswood, Premier, Sandman, One Tonner, Statesman or WB ute, chances are you&#8217;ve either experienced cooling system problems or know someone who has. When these cars rolled off the production line in [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":3473,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_uf_show_specific_survey":0,"_uf_disable_surveys":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":false},"categories":[1],"tags":[],"class_list":["post-7322","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.7 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>HQ, HJ, HX, HZ and WB Radiator Upgrade Guide - 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