OZ trans problems

[83hurstguy]

New member here... Don't have a GN (yet) but am currently playing around with an '83 Hurst/Olds... Been reading these forums for a long time b/c this seems to be the best place I have found for 200-4R info as well as chassis info.

Anyways, I have owned my H/O for about 3500 miles, and the car has 94,000 total miles on it. Supposedly the trans was "rebuilt" at 85,000, and I see grease markings on the top of the trans as a label like it had been pulled out. Ever since I have gotten it, the trans has had a multitude of problems... when I got it home, nobody had ever adjusted the TV right, just taking your foot off the brake and letting it idle down the street would shift it into 2nd, and it would be in O.D. by like 20 mph if I remember correctly. Anyways... the problems...

First, it clunks extremely loud whenever going from park to in gear (or rev. to drive, etc...) There are times I hear a soft clunk coasting up to a stop sign and it downshifts. Car has a brand new driveshaft with all new joints and yokes, a newly rebuilt 8.5" diff, and new trans and motor mounts. What causes this?

Second, the car always shifts extremely late and hard on a part throttle 1-2 shift, 2-3 isn't as bad... unless you really get your foot into it, in which case it shifts nice and mushy. It has done this no matter how I adjust the T.V. cable, although it feels like adjusting the T.V. changes it a little bit.

Third, I have a feeling that the correct valve body is out of the trans, since the car always upshifts by 4500 rpm if just left in drive and your foot is on the floor. How do I check the valve body to see if its correct?

Sorry for the long post... I would appreciate any input from anyone who can help.

Thanks!

Luke

 

[chris718]

ok the first thing is the valve body is set up to shift at about 4800 rpms at wot from the factory.swapping to the gn or ss gov will raise the shift points another 400 rpms the other problems sound like the accumulator valve in the valve body has been screwed with,also soft shifts at wot are a calibration eror installed by gm at the factory.our valve body kit will remove these errors and create superior shift quality and throttle sensitive pressure rise making it work like a champ.we also have a 200 page manual on the transmission loaded with calibration info if you want to attempt it yourself.the kit should be considered mandatory.if the trans has good friction elements the kit will only make it work better.

 

[83hurstguy]

Thanks for the input... I see how that will help with the shifting problems...

Any other input on how to fix that clunk from the trans? Found out also that first gear has what sounds like a bit of bearing whine to it... Looks like this thing is a real p.o.s.... complete rebuild time?

I found a complete original OZ tranny that I could buy that is supposed to be in perfect working order... might have to just buy that and put it in for now b/c it looks like fixing mine is gonna be $$$$$

 

[chris718]

clunk can be a worn sun shell or a valve body problem .thats why i suggestred the kit.grab that other trans they are hard to find.do you know of any olds hurst sights i can view.?

 

[83hurstguy]

www.realoldspower.com and www.oldspower.com really have no guidance when it comes to 200-4R transmissions... A lot of people buy cheap "kit" transmissions and have a ton of problems with them. I have seen your advice from this site so I usually recommend people come over here or to directly check out your website and contact you. rop has a trans section... oldspower usually just has trans info mixed in with its RWD olds info. If you stopped by and checked up on those sites every couple days or so, you would help out a ton of people and hopefully gain some business.

Thanks again for the help... I am currently a student and trying to do this the economical way, looks like its gonna add up fast... so, as of right now, I would need your manual, your valve body kit, and what else? to start trying to fix this thing...

 

[chris718]

i think the maqnual and the valve body kit are both wise decisions.thanks for the links and if i can help further let me know

 

[Hacksaw]

Luke:

For what it's worth, there's a 200-4R rebuild tips section at:
http://www.montecarloss.com/SSThunder/drivetrain.html

I have another one as well, but since that one sells built transmissions I better not post it. I'd still buy a trans good book.

That clunk could be motor mounts or u joints. Easier to check these than dig into the trans. If you have whirring in first gear only, then a bearing could be bad inside. :frown:

My brother inherited my mother's 1985 T Type (that car was way too hot for her needs). The second gear kept slipping (fluid cavitation? He drove it hard), then the whole trans died. So, he got a wrecking yard unit, & exchanged that ultra rare 200-4R as a core!!

Man, that valve body is $500-600 new, if you can find one. Yes, a valve body kit can make up for some of differences, but like one Tech guy told me, the GN/GNX/T Types still are the best valve bodies, hang onto them. The governor is like $125 (hi RPM shifts, cut down weights, it's more than just that spring that's different from other 200-4Rs!), and that servo is $165 from GM, although the aftermarket ones are slightly cheaper & better at this point, IMHO.

Grab that model OZ 200-4R!!

So, when I get my father's 1987 GN I'm hanging onto that trans. And when it's rebuilt, I'm making darn certain they don't swap it for some other 200-4R!


-Mike H.

 

[83hurstguy]

I appreciate the help there guy.

I bought Chris's 200-4R manual and valve body kit It should be going in this weekend. It is quite possible that the correct valve body is still in the trans and somebody just messed with it or drilled the separator plate... will all be discovered this weekend.

Chris's manual and kit look very nice. I am glad I got the manual along with the valve body kit. The manual's instructions are a lot more thorough for the project.

Got brand new motor and trans mounts, along with a new drivershaft and rearend... clunk is in the trans