Transmission cooler lines from 4L60E - The 1947 - Present Chevrolet & GMC Truck Message Board Network

BlueJeep · 11-21-2013, 12:13 AM

What are you guys doing for transmission cooler lines on the 4L60E? My preference is the good 'ole 5/16" hard line, but the fittings are not the same NPT thread where they screw into the transmission. I'm not looking to convert to AN and run braided lines, not my thing. Is my best option to buy the dies to be able to duplicate the GM flare on some hard lines and run the OEM fittings in the tranny? I do have the Mastercool flare tool so I think this is an option for me. Are there fittings available to just use double flared lines?

Thanks!

**dayj1** · 11-21-2013, 12:58 AM

The AC Delco part number for the fitting that you want is 8637742. It is a brass fitting that screws into the trans case (after you remove the quick connect fittings) and has the correct thread for 5/16 double flare hard lines.

**dayj1** · 11-21-2013, 01:34 AM

The Dorman part number for the fitting above is 800755. They should be able to get that at any of the chain parts stores.

clinebarger · 11-21-2013, 01:57 AM

Quote:

Originally Posted by BlueJeep

What are you guys doing for transmission cooler lines on the 4L60E? My preference is the good 'ole 5/16" hard line, but the fittings are not the same NPT thread where they screw into the transmission. I'm not looking to convert to AN and run braided lines, not my thing. Is my best option to buy the dies to be able to duplicate the GM flare on some hard lines and run the OEM fittings in the tranny? I do have the Mastercool flare tool so I think this is an option for me. Are there fittings available to just use double flared lines?

Thanks!

Most GM transmission use 1/4" NPSM.

BlueJeep · 11-21-2013, 07:35 PM

Thanks guys! I was under the impression that earlier transmissions (pre quick-connect) had NPT fittings, good to know they're all NPSM.

11-21-2013, 12:13 AM	#1
BlueJeep Registered User Join Date: Mar 2008 Location: Waukee, Iowa Posts: 1,608	Transmission cooler lines from 4L60E What are you guys doing for transmission cooler lines on the 4L60E? My preference is the good 'ole 5/16" hard line, but the fittings are not the same NPT thread where they screw into the transmission. I'm not looking to convert to AN and run braided lines, not my thing. Is my best option to buy the dies to be able to duplicate the GM flare on some hard lines and run the OEM fittings in the tranny? I do have the Mastercool flare tool so I think this is an option for me. Are there fittings available to just use double flared lines? Thanks! __________________ build threads: 86 Suburban 88 Jeep 6.0 swap 49 Chevy truck 54 Chevy wagon 86 Suburban lowered 4/6 54 Chevy wagon 49 Chevy/s10 mix 88 Jeep Wrangler rockcrawler

11-21-2013, 12:58 AM	#2
dayj1 Senior Member Join Date: Jul 2009 Location: Athens, AL Posts: 499	Re: Transmission cooler lines from 4L60E The AC Delco part number for the fitting that you want is 8637742. It is a brass fitting that screws into the trans case (after you remove the quick connect fittings) and has the correct thread for 5/16 double flare hard lines.

11-21-2013, 01:34 AM	#3
dayj1 Senior Member Join Date: Jul 2009 Location: Athens, AL Posts: 499	Re: Transmission cooler lines from 4L60E The Dorman part number for the fitting above is 800755. They should be able to get that at any of the chain parts stores.

11-21-2013, 07:35 PM	#5
BlueJeep Registered User Join Date: Mar 2008 Location: Waukee, Iowa Posts: 1,608	Re: Transmission cooler lines from 4L60E Thanks guys! I was under the impression that earlier transmissions (pre quick-connect) had NPT fittings, good to know they're all NPSM. __________________ build threads: 86 Suburban 88 Jeep 6.0 swap 49 Chevy truck 54 Chevy wagon 86 Suburban lowered 4/6 54 Chevy wagon 49 Chevy/s10 mix 88 Jeep Wrangler rockcrawler



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