T150 And Dana 20 Gear Lube Transfer Problem

This relates to the T150/Dana 20 combination that was installed in the 1976 - 1978 CJ5, CJ6, and CJ7.

Unlike some other trans/transfer combinations, the gear lube in this trans/transfer combination is not supposed to move between the transmission and transfer. But it does, resulting in too much lube in the transfer case and not enough lube in the transmission. When the fill plug on the transfer is removed lube shoots out.

I’ve read lots about it online. Some of it is contradictory. I need some clarification on the procedure to correct it.

Jeep issued a Recall Campaign on April 11, 1978 for this issue. I have a copy of that recall. As I understand it, the problem resulted because the seal was incorrectly installed, installed backwards, at the factory.

According to the Recall notice, the solution is to remove the old seal and install a new one correctly. And then install a new gasket. The Recall says nothing about plugging holes in the case(s).

However, I’ve read in older threads online that the solution should also include plugging a hole or holes in the transmission case.

I’ve also read that there may be different gaskets, some that cover the case holes and some with holes cut out at those locations.

My question is: is it sufficient to replace just the seal and the gasket, or is it necessary to plug holes in the cases as well? Thanks, Jack

 

Just do what the recall states, nothing more, nothing less.
It was called TranLub recall. or something like it.
Seems about 50% we checked had the problem.

 

Excellent, that's what I was hoping to hear. Yes, it was called TRANLUB Repair (Type S Product Recall) Diagnosis and Repair Bulletin No. 8-02 dtd April 11, 1978. For some reason I can't copy the link, but I found it on olijeep.com Thank you! Jack

 

This post brings back bad memories. After finishing my restoration of my 79 CJ-5 I had constant fluid transfer issues. Within a few miles my transfer case would be puking oil and my transmission would be dry. Ended up dropping the transmission five different times before I fixed the issue. Long story short, cheap quality seal replaced and I had a missing slinger & fiber washer. There are some part numbers and TSB information about the various differences with the T-150 here:

https://www.jeepforum.com/threads/t150-fluid-draining-into-dana-20.3476346/page-2

So to answer your question, yes I'd seal up those ports and make sure your vents are clear. New rear seal + gasket *should* resolve your issue assuming you aren't missing parts like I was. I suspect this is why one of the previous owners had used a gallon of RTV to mate the transmission / transfer together.