Rear disc conversion complete :)

[karstman]

Finally got to complete my rear disc conversion . I used a set from a 98 Grand with a D44A, not a D35. Everything went according to plan and the results seem to be well worth the effort. Hopefully I can get the TJ on a trail next weekend and really see how they perform.

A few notes from the install....the D44A disc assemblies work perfect. All procedures were identical to using a set of discs off a D35C. I broke my double flaring tool trying to flare the pass side line. Rather than hunt down another tool, we ran out and purchased a 30" length and a 12" length of pre-flared brake line. It cost all of 4 bucks and saved a ton of time, which we were running out of. I just grabbed my small tubing bender and shaped the lines to mimic the factory lines.

Thanks to Matt (overkill) for the help with the install, and Stu, Blaine, and Frank for the info and custom retainer plates.

later,
mark

[StealthTJ]

So you still needed the custom retainers, even though you got a setup from a ZJ D44 ?? Didn't know for sure if you would or not.



Fred

[karstman]

Yes, you still need Blaine's retainer plates. The ZJ D44A uses the same disc brake setup as the D35. It also uses c-clips to retain the axles so it has no retainers of it's own.

later,
mark

[PK99TJ]

So does that mean you and Matt are even or what? Hehe. That's great Mark, Congrats! Having sand blasted a tiny bit of it, I can say I "chipped in". :-)

[StealthTJ]

Ahhhh, I didn't realize that the ZJ's D44 were C-cliped
I did the conversion almost a month ago, and it made a *HUGE* difference, especially with the auto I can stop again
I had a couple of little tweaks that I had/have to do to mine. The lip on the retainers were a little too long, and, when tightened, were up against the seal and bearing hard enough to impead the axle turning and scruching the seal. I took it to the best diff shop in town, (they do almost all of the local race cars and a lot of the 4x4 grearing).. They shimmed it a little bit and it's fine now. They were impressed with those customer spacers/retainers. Thought it would make a nice kit to market, just supply some thin shims to account for the differences in some of the axles.
I'm also changing the combo valve in mine out completely. I'm getting one from MP Brakes for disk/disk. Even after removing the O-ring, I'm getting a few pounds of pressure holding the pads against the rotor a little more than they should be. I just noticed that last week, when, after driving around a lot, I noticed that the lug nuts on the rear tires were almost too hot to touch.
The pads don't drag much, but they do enough to heat things up after a while.
Removing the O-ring from the combo valve appears to "correct" the proportioning but doesn't seem to affect the residual pressure. Combo valves for drums (rear) are set up to hold a few pounds of pressure against the shoes to keep them closer to the drums.
Anyway, mine are great !!! After a couple of trips out wheeling after the auto swap and still with the rear drums, the new rear disk are a God send



Fred

[Daddy Longlegs]

Fred,

Let me know how the MP prop valve works for you.

Thanks,

[StealthTJ]

Scott, are you getting a little rear disk hold on from the factory combo switch also ??


Fred

[Daddy Longlegs]

I'm not sure. I did a bunch of research on the factory prop valve and there is an integrated residual valve to the rear brakes that cannot be removed from what i can tell. I think it may be making th e brakes drag just a little.

[StealthTJ]

Yup, that's as I would have expected. I didn't look into the factory valve, but that's the way disk/drum valve usually work. They hold about 10 lbs of residual against the rear drums to keep the shoes closer to the drum. My rear disk drag is fairly light, but enough to heat things up if you drive far enough.


Best,
Fred

[mbryson]

Originally posted by karstman
Yes, you still need Blaine's retainer plates. The ZJ D44A uses the same disc brake setup as the D35. It also uses c-clips to retain the axles so it has no retainers of it's own.

later,
mark

Question::::.......maybe I'm a little behind here....I've been working at work {sssshhhhh, don't tell anybody}. Is Blaine 'the man' and making up retainer plates? If SO, I need to get a hold of him. I'm already tired of the 'weekly adjusting' to the D44 drums.