I finally pulled apart my 80e that I built around 3 years and 25,000-30,000 miles ago. My only complaint with the trans was a lack of reverse and transbrake when the unit got up to operating temp. I correctly assumed pump wear from low overall line pressure, confirmed at tear down.



This is a home-built, late-case (02'), unit with a CK brake, a number of upgraded hard parts, and its dual-fed along with typical lube mods. The entire unit had been torn down and inspected and the only real odd issue I came across was excessive wear on the direct drum from the 4th (bottom most) center support sealing ring. The 1st and 3rd ring areas show some typical polishing, but the wear is immeasurable. This 4th ring, however, shows significant grooving and wear that I have never seen before on its own.







The clutches/steels throughout the unit, and the directs, are all like new. And the sprag itself, and its journal, are also in perfect health. I am planning on mending the drum with a Sonnax sleeve kit (34838-01K), as being a 36 element drum it makes fiscal sense too, but I want to make sure this doesn't happen again.

Is there any specific cause that could have accelerated this wear? And what would need to do in order to prevent this from happening again? The unit had plastic style sealing rings on the center support, that I have never had a problem with, and a press fit sungear shaft, that was confirmed concentric to the drum after installation.

 

Typical wear in this area of drum is bad bushings in reaction tube or center support . But also if used I have noted over the years some reman drums seem to dislike the metal sealing rings some want you to use. But the wear is the REV/BRAKE ISSUE. I cant tell much about the pump in photo but generally if you can feel it then it bad enough to replace.

 

The pump was absolutely destroyed. Bushings in reaction tube and center support are still like-new. This was also a brand new aftermarket drum using plastic center support sealing rings.

The only wear is the bottom land from the center support, the others barely even polished the surface.

The drum is already machined and I am awaiting delivery of the sleeve kit.

 

This is a common wear and tear location when using a Post Torque-Converter Dump with a Trans-Brake...

 

Is this something than can be remedied hydraulically? Admittedly I am not well versed in trans brake specific fluid circuitry. This is a CK trans brake application which, from what I can tell, is significantly less refined than the Jake's unit.