Transmission Cooler Upgrade-Fitting Swap Question

[pushpole]

I'm upgrading the tranny cooler to the Long H7B Cooler that Ranch55 used. My question is in swapping the quick disconnect fittings. What sealant should I use on the 1/2" NPT end? Is teflon paste OK with transmission fluid?
Thanx

[Robyn]

The big issue with the tranny is to be sure you dont get anything into the oil flow that can get hung in a valve.
The paste should be fine. Just be sure to keep the stuff back on the threads a couple so you dont get any into the oil flow.
(Tape is a NO NO )

I have even used Permatex on threads and had zero issues.

This is one area that I get very anal about. The valves in the auto trannies run with very little clearance and any foriegn material can stick a valve and cause all sorts of issues.
One of the best things you can do for you little friend is to install a spin on oil filter in the return line to the tranny. (Kits available and look like regular oil filter)
You can swap these out every couple of engine oil changes and then add a little fluid to top things off.
The stock filters in the pan are basically a clod sifter.
The converter in an auto tranny is the biggest single source of crud and from the converter the oil flows to the coolers and then back to lubricate many of the components and then to the pan and back into the system.
The extra filter can and does help extend the life of these units and in tandem with a bigger cooler is $$$$$$$$$$ well spent.:D:D:D:D:D

The oil coolers act like a huge filter and will over time collect crap and then when the oil is changed the fresh fluid will cut the stuff loose and send it all back to the tranny. :eek:

Good luck

Robyn

[killerbee]

That was very detailed, but he already has a spin on filter. Adding another will add resistance and reduce flow in the cooling circuit; just the opposite of what a larger TOC needs.

[Robyn]

Hmmm
I was not aware that any of the current rigs came with a spin on tranny fiter???
If it does thats great. Or did he add the filter???

Any way Its all good as long as it keeps the crud out.:)

Robyn

[killerbee]

the allison has always been outfitted this way, from 01. I am not an expert, but maybe that is part of its longevity secret. it is upstream of the TOC.

I am experimenting with larger TOC's right now.

[More Power]

Is teflon paste OK with transmission fluid?


Sure it is!

I recommend people run in Tow/Haul whenever the trans temps climb above 210. The torque converter clutch will lock in 2nd through 5th (or 6th for the 06 & newer), which will reduce the heat buildup due to an unlocked TC.

You're likely to see higher temps while in town, driving stoplight to stoplight, or while towing heavy in the mountains at reduced speed. For either situation, T/H will help a lot and may remove any need for a larger transmission ATF cooler.

Jim