Transmission Port Thread<\/strong><\/td>\n1\/4″-18 NPSM straight thread (not tapered NPT) \u2014 confirm before ordering adapters<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\nDescription<\/h2>\n<\/p>\nAbout this item<\/h2>\nWorried about heat and chemical breakdown in your transmission lines? This 6AN PTFE transmission oil cooler line<\/strong> kit delivers a 1500 PSI-rated, PTFE-lined hose with 304 stainless braid and nylon cover for GM 4L60, 700R4, TH350 and TH400 builds. Two 7FT lengths let you plumb both the feed and return runs from one transmission oil cooler kit<\/strong>, cut to fit your own chassis and cooler position.<\/p>\n![\"](\"data:image\/svg+xml;base64,PHN2ZyB3aWR0aD0iMSIgaGVpZ2h0PSIxIiB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciPjwvc3ZnPg==\") <\/p>\n
Where is this 6AN transmission oil cooler hose applied?<\/h3>\nUse this transmission oil cooler hose<\/strong> on GM 4L60, 700R4, TH350 and TH400 transmissions wherever a chemical-resistant, high-heat connection between the transmission and an external cooler is required \u2014 hot rod and muscle car builds, engine swaps, track cars, and tow rigs adding an auxiliary core. The factory hard line on these transmissions is 3\/8″ OD, which corresponds directly to -6AN, so this hose matches the flow the automatic transmission oil cooler<\/strong> circuit was designed around rather than over- or under-sizing it. At 7FT per length there is enough hose for a front-mounted cooler with routing slack to spare.<\/p>\n<\/p>\n Why PTFE + 304 stainless + nylon?<\/h3>\nRubber and push-lock hose absorb ATF over time, then swell, harden and eventually weep at the barb \u2014 the same aging that ruins factory lines. The PTFE inner tube here is chemically inert: it resists nearly all automotive fluids including E85 and race fuel, does not swell, and does not go brittle from years of heat cycling. The 304 stainless steel braid holds 1500 PSI working and 4500 PSI burst pressure and keeps the line from ballooning when hot. The braided nylon outer cover handles abrasion where the line passes near headers, the crossmember or the frame. Together they perform from -76 \u00b0F to 446 \u00b0F, well beyond the point where a 250 \u00b0F-rated transmission oil cooler hose<\/strong> starts to fail.<\/p>\n<\/p>\n What thread do TH350, TH400, 700R4 and 4L60 cooler ports use?<\/h3>\nThe case ports are 1\/4″-18 NPSM \u2014 a straight thread that seals against a washer, not tapered NPT. This catches out a lot of builders, because NPT looks similar and will start to thread in, then wedge as it tightens and risk cracking the case. NPSM torques to roughly 25 ft-lb against its sealing washer. Start every fitting by hand and stop as soon as it feels tight. Some pre-1976 TH400s have a 5\/16″ inverted flare adapter already installed; remove it and the NPSM port is underneath.<\/p>\n Package Contents<\/h3>\n\n- 2 \u00d7 7FT 6AN PTFE transmission oil cooler hose<\/li>\n
- Swivel hose ends<\/li>\n
- Adapter fittings<\/li>\n<\/ul>\n
<\/p>\n\nHow to Install a Transmission Oil Cooler and Cooler Lines<\/h2>\n<\/p>\n The hose runs between the transmission and the transmission cooler \u2014 that single connection is the whole job. Before you install transmission oil cooler<\/strong> plumbing, identify the two cooler ports on the case. The forward port is the outlet carrying hot fluid toward the cooler; the rear port is the return. Getting these backwards is the most common mistake in a first-time transmission oil cooler installation<\/strong>, so mark them before anything comes apart.<\/p>\nTransmission oil cooler installation instructions<\/h3>\n\n- \nMount the cooler.<\/strong> Position it ahead of the radiator or condenser where it gets clean airflow, and secure it to solid structure rather than to the radiator core itself.<\/li>\n
- \nFit the case adapters.<\/strong> Thread the 6AN to 1\/4″-18 NPSM adapters into both ports with their sealing washers, by hand first, then to roughly 25 ft-lb.<\/li>\n
- \nMeasure the routing.<\/strong> Run a length of string along the exact path each hose will follow. Add about 10% for slack, and remember the 3.5″ minimum bend radius \u2014 every direction change consumes length.<\/li>\n
- \nAssemble and cut the hoses.<\/strong> Tape the cut point so the braid cannot flare, cut square, blow the liner clean, then fit the sockets and olives. This is the core of how to install transmission oil cooler lines<\/strong> correctly \u2014 a clean square cut is what makes the seal.<\/li>\n
- \nRoute and secure.<\/strong> Keep the lines clear of headers, exhaust, steering components and moving suspension. Add cushioned separator clamps every 12-18 inches so nothing chafes.<\/li>\n
- \nFill and check.<\/strong> Top off with fresh ATF, run the engine through the gears, then check every fitting for weeps after the first full heat cycle and again after the first drive.<\/li>\n<\/ol>\n
Most questions about\u00a0how to install automatic transmission oil cooler<\/strong> plumbing come down to two things: confirming the thread type at the case, and deciding whether to keep the radiator cooler in the loop. Keep it in most builds \u2014 it warms fluid on cold starts and does more cooling work than people expect. The standard path is transmission out, through the radiator cooler, then through the auxiliary cooler, then back to the transmission.<\/p>\nWhy Choose the 6AN 7FT PTFE Transmission Oil Cooler Kit?<\/h2>\n\n- \nGM 4L60 \/ 700R4 \/ TH350 \/ TH400 Fitment:<\/strong> Sized to -6AN, matching the 3\/8″ OD factory line these transmissions were designed around.<\/li>\n
- \nPTFE + Stainless + Nylon Build:<\/strong> PTFE liner for chemical resistance, 304 stainless braid for 1500 PSI strength, nylon cover for abrasion and heat protection.<\/li>\n
- \nTwo 7FT Lengths:<\/strong> Enough hose for both the feed and return runs, cut to fit your chassis instead of working around fixed-length lines.<\/li>\n
- \nReusable Swivel Ends:<\/strong> Assemble by hand with ordinary tools \u2014 this transmission oil cooler installation kit<\/strong> needs no crimping press, and the ends can be re-clocked if routing changes.<\/li>\n
- \nBuilt to Outlast Rubber:<\/strong> No swelling, no hardening, no weeping barbs \u2014 the failure modes that make transmission oil cooler repair<\/strong> a recurring job on rubber hose.<\/li>\n<\/ul>\n<\/article>\n","protected":false},"excerpt":{"rendered":"
Specifications 6AN PTFE Transmission Oil Cooler Line Ki […]<\/p>\n","protected":false},"featured_media":1384,"comment_status":"open","ping_status":"closed","template":"","meta":[],"product_brand":[],"product_cat":[128],"product_tag":[113,56,142,131,132,133],"class_list":["post-1390","product","type-product","status-publish","has-post-thumbnail","product_cat-transmission-oil-cooler-hose-kits","product_tag-hose-line","product_tag-new","product_tag-ptfe-fuel-line-kits","product_tag-transmission-oil-cooler-hose","product_tag-transmission-oil-cooler-hose-kits","product_tag-transmission-oil-coolers","first","instock","purchasable","product-type-simple"],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.jlinlin.com\/index.php\/wp-json\/wp\/v2\/product\/1390","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.jlinlin.com\/index.php\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/www.jlinlin.com\/index.php\/wp-json\/wp\/v2\/types\/product"}],"replies":[{"embeddable":true,"href":"https:\/\/www.jlinlin.com\/index.php\/wp-json\/wp\/v2\/comments?post=1390"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.jlinlin.com\/index.php\/wp-json\/wp\/v2\/media\/1384"}],"wp:attachment":[{"href":"https:\/\/www.jlinlin.com\/index.php\/wp-json\/wp\/v2\/media?parent=1390"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/www.jlinlin.com\/index.php\/wp-json\/wp\/v2\/product_brand?post=1390"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/www.jlinlin.com\/index.php\/wp-json\/wp\/v2\/product_cat?post=1390"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/www.jlinlin.com\/index.php\/wp-json\/wp\/v2\/product_tag?post=1390"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}} | ![\"](\"https:\/\/cdn.shopify.com\/s\/files\/1\/0590\/5403\/0984\/files\/A_01_a9881b46-6b77-4fad-bf43-6d0276d8e86c.jpg?v=1786011489\")
<\/p>\n![\"6AN](\"https:\/\/cdn.shopify.com\/s\/files\/1\/0590\/5403\/0984\/files\/A_03_09e14855-1dc0-4f3c-9b84-695a2a44e782.jpg?v=1786011488\")
<\/p>\n![\"Swivel](\"https:\/\/cdn.shopify.com\/s\/files\/1\/0590\/5403\/0984\/files\/A_02_16751cf4-d177-4990-9247-521d07c8689f.jpg?v=1786011489\")
<\/p>\n![\"What](\"https:\/\/cdn.shopify.com\/s\/files\/1\/0590\/5403\/0984\/files\/A_05_6de421a4-1d7d-4339-992a-07bb60411798.jpg?v=1786011488\")
<\/p>\n![\"Correct](\"https:\/\/cdn.shopify.com\/s\/files\/1\/0590\/5403\/0984\/files\/A_04_ce3a7687-4916-47b8-a441-4d91bc28f647.jpg?v=1786011488\")
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