fox1999

I have a 1985 gsl. Theres a lot of rotational play in the driveshaft from the transmission to the rear differential, about an inch, and the driveshaft makes a clunk noise when i release the clutch because of how much play it has. I drained the oil in the rear differential and saw metal grains so im assuming im gonna need to replace it fairly soon lol. Does anyone know any good resources i can get a newish differential or a rebuild kit? Also my clutch gets skippy and jumpy when im easing off the clutch sometimes and i believe the person selling it said it was a new clutch. Does anyone know anything about that?

fox1999

Actually just the slave cylinder was replaced but its not slipping or anything its just skipping alot

diabolical1

iTrader: (3)

for the clutch, what do you mean by "skipping"? can you describe.

for the rear end, are you absolutely sure there's nothing wrong with the driveshaft itself (bad u-joint)? seeing metal in and of itself is not completely abnormal especially if you don't know if the maintenance was kept up with. as long as we're not talking about chunks or large bits, it may be okay. i don't know because i didn't see it, but just keep it in mind.

if the rear is going bad, then it can be rebuilt. for parts, obviously check the usual suspects first: Mazdatrix, RB, Atkins, etc.. replacing the entire rear is an option, but from what i've seen in casual glances, they are not cheap (used to be able to get one between $100-200) any more. i don't know how much it costs to rebuilt one since i've never had to do it.

here are some links:

https://www.rx7club.com/1st-generati...torial-711712/

https://www.rx7club.com/1st-generati...advice-871945/

https://www.rx7club.com/1st-generati...build-1021713/

https://www.rx7club.com/1st-generati...ential-355326/

now, with all that said ... i just read your other thread, so are you fixing this or replacing it with Gen 2 parts? is your Gen 2 swap idea because you think you might not be able to fix it? just trying to understand.

fox1999

Im pretty sure the driveshaft is fine, its just got a little surface rust on the U joints, what i meant by the the clutch skipping and jumping was when i ease off the clutch it will start non consistently trying to catch causing the vehicle to sometimes violently thrash you back and forth. The metal in the oil was just small grains i could feel and see between my fingers a bit smaller than a 4th of a grain of rice. I was thinking of trying to make it last till i come up with the money for a rear end conversion to the fc suspension. I want to swap it because I like how the car looks but i want the performance.

KansasCityREPU

iTrader: (9)

"violently thrash you back and forth" could be a few things. It could be the throw-out bearing getting stuck, bad clutch slave, U-joint, rearend, trans, or clutch soft line not allowing fluid back.

If you don't know when the clutch master/slave/soft line have been replaced I would start there. Each and easy and good preventative maintenance. It's sometime hard to tell when a u-joint is bad. They can be frozen. They are a little more tricky to fix because they are staked but can be replaced. The rear end and clutch get a lot more involved and cost goes up.

fox1999

Well the slave cylinder just got replaced to my knowledge. Thats what the previous owner claims. The transmission makes a whining noise in 1st 2nd and 3rd mostly, that's after it heats up. I just replaced the fluid and its still doing it. Thats the only odd noise it makes. Or actually it rarely makes a clunking noise when i take it out if gear sometimes. But the whole car will skip forward when im easing off the clutch and ill push it back in then drop it a little faster to make it catch better but not dumping the clutch of courseits almost like the clutch isnt even sometimes.

diabolical1

iTrader: (3)

do you know what type of clutch is in it? (sprung vs. unsprung)

fox1999

Im not sure, i also don't know if or when it was replaced, it must've been replaced at some point, the car has quite the amount of miles on it.

KansasCityREPU

iTrader: (9)

Do the RPMs increase without the car moving faster during this action? This could indicate a slipping clutch. This is a hard one without inspecting parts.

fox1999

Not really, not until i get on the freeway amd it feels like more of a horsepower issue.

KansasCityREPU

iTrader: (9)

Your clutch could be slipping.

fox1999

Yeah maybe. Im noticing now that i have to lift up kinda far before it catches.

GtiKyle

iTrader: (5)

Or the clutch pedal isn't adjusted correctly. You can find the procedure and specification in a Haynes manual. If you don't already own one, they're great resources.

KansasCityREPU

iTrader: (9)

You can get the factory service manual here for free: Foxed.ca