I'd like to say something about the T-5
LanceMaster
Jeeper
- Posts
- 18
- Thanks
- 2
- Location
- Seattle, WA
- Vehicle(s)
- 1985 CJ7
Howell Throttle Body Injection
305,000 miles. Engine rebuild at 196,000.
NV3550 trans, D300 Transfer
2.5" spring lift
Yukon axles
Custom rust
In a T-5 use synthetic GL4 lube ONLY!
The T-5 is inherently week, mainly due to it's bearing and journal design. BUT it is ok for moderate 4-wheeling, behind a 6-cylinder, given proper lubricant!!! Here's what I found;
Not long after I bought my CJ7 I was doing routine maintenance. I went to a Jeep parts dept and asked them what trans lubricant I should use. He said to use normal 75w90 gear oil, so I did. Dumb me.
About a year later I lost 4th gear. So I pulled the trans and took it to a specialty shop for a rebuild. When I picked it up I asked them what lube should I use? They said because it was an aluminum case transmission I should use ATF. Hmmmm, ok.
A couple years later this rebuild got so loose I had to pull it again. This time I drove a couple hundred miles and exchanged it for a remanufactured transmission, not a rebuilt. (yes, there is a difference). Again, I asked them what lube should I use? They should know right, and they too said because it was an aluminum case transmission I should use synthetic ATF.
BTW, on both rebuilds I noticed the input shaft had very, very minor play in it. 1000th's of an inch maybe but enough for me to take notice.
UGH! A couple years later I lost 2nd gear!!!
All of these were bearing related failures.
This time I found a very good rebuild manual and did it myself. Guys, it's not that hard if you have a good manual, tools and patience. I also set the input shaft bearing clearances tight, but within specs, and it still didn't feel right so I shimmed it just a teeny tiny bit tighter to where it felt better.
Here's what else I found: after hours and hours of searching I found a small note on a trans conversion/rebuild web site that said to ONLY USE GL4 lube in the T-5. NOT GL5 that is backwards compatible, NOT ATF, NOT regular gear oil. HAS TO BE GL4.
After my own rebuild I used Redline MTL which is a synthetic GL4 specific, and went almost 10 years without T5 problems again. I enjoy finding old skidder roads in the Cascades mountains so the T5 took some punishment and held up.
I only switched to a NV3550 because the snap ring holding 5th gear in place slipped out of the grove in the mainshaft and I already had an NV3550 a guy gave away.
In the T-5, use synthetic GL4 lube ONLY!
The T-5 is inherently week, mainly due to it's bearing and journal design. BUT it is ok for moderate 4-wheeling, behind a 6-cylinder, given proper lubricant!!! Here's what I found;
Not long after I bought my CJ7 I was doing routine maintenance. I went to a Jeep parts dept and asked them what trans lubricant I should use. He said to use normal 75w90 gear oil, so I did. Dumb me.
About a year later I lost 4th gear. So I pulled the trans and took it to a specialty shop for a rebuild. When I picked it up I asked them what lube should I use? They said because it was an aluminum case transmission I should use ATF. Hmmmm, ok.
A couple years later this rebuild got so loose I had to pull it again. This time I drove a couple hundred miles and exchanged it for a remanufactured transmission, not a rebuilt. (yes, there is a difference). Again, I asked them what lube should I use? They should know right, and they too said because it was an aluminum case transmission I should use synthetic ATF.
BTW, on both rebuilds I noticed the input shaft had very, very minor play in it. 1000th's of an inch maybe but enough for me to take notice.
UGH! A couple years later I lost 2nd gear!!!
All of these were bearing related failures.
This time I found a very good rebuild manual and did it myself. Guys, it's not that hard if you have a good manual, tools and patience. I also set the input shaft bearing clearances tight, but within specs, and it still didn't feel right so I shimmed it just a teeny tiny bit tighter to where it felt better.
Here's what else I found: after hours and hours of searching I found a small note on a trans conversion/rebuild web site that said to ONLY USE GL4 lube in the T-5. NOT GL5 that is backwards compatible, NOT ATF, NOT regular gear oil. HAS TO BE GL4.
After my own rebuild I used Redline MTL which is a synthetic GL4 specific, and went almost 10 years without T5 problems again. I enjoy finding old skidder roads in the Cascades mountains so the T5 took some punishment and held up.
I only switched to a NV3550 because the snap ring holding 5th gear in place slipped out of the grove in the mainshaft and I already had an NV3550 a guy gave away.
In the T-5, use synthetic GL4 lube ONLY!
