The Stovebolt Site Forums The Shop Area Engine Shop fluid choices for my t-5 ?

I finally found a T -5 to put behind my 235 , thanks for all the help. I couldn't do it without all of the input from you guys. I have read a lot on the web about people using auto trans fluid ? I put 80-90 oil ( not synthetic ) what is the best choice ?

Run the numbers on your T5 to see if it is a world class. It may have a sticker on it with recommendations for the type of fluid, you should follow them. Check out this site.
http://www.britishv8.org/Articles/Borg-Warner-T5-ID-Tags.htm

I have a non-world class T-5 from an '89 S-10 and also run Dexron II as per the '89 Chev shop manual. As was stated above, run the numbers to identify the vehicle it came from, then get a manual for it and read what it says about the tranny lube. I found the '89 Chev manual at the public library.

There has been some questions raised about the T5 lubricant so being who I am.......I've run the 80-90 weight in my used NWC (brass synchro rings) T-5 for the past 10,000 miles. It had gear lube in it initially and when I first drained and checked it for metallic particles both ferrous and non-ferrous, I found none. The transmission shifts smoothly, is quiet and the only difference I've noticed is that when the temperature gets down into the 40-50's before the engine warms up, the cold transmission shifts are initially a little stiffer. Having checked for metals at 5000 miles I found none.

On a used NWC (brass syncro rings)Hybrid Camaro T5 for my next project, the transmission came with Dextron ATF. Ditto on the negative check for metals in the fluid. I refilled that with Royal Purple SyncroMax which is a fluid recommended for the WC boxes.

Not wanting to open a can of worms on the forum......I will continue to use the gear lube in my truck box because of the normal operating temperatures here in sunny Florida and will run the RP SyncroMax (ATF)in my NWC Hybrid box. IMO.....the WC T5 with needle bearings and synthetic synchronizers requires ATF, while in temperate climates the gear lube OR ATF would keep your T5 happy. That's my story and I'm sticking to it!

Dave

I've got an 85-86 T-5 in my 37 Chevrolet 1/2 ton pickup truck. I also have a 1985 S-10 Chevrolet Blazer Owner's Manual that specifically indicates that Dexron II, which has now morphed into Dexron III, is to be used in that particular T-5 NWC transmission.

I've tried them both & have settled on the ATF.

Amsoil Synthetic SAE 50 in mine in a variety of well beaten and abused vehicles.