Hey guys so I’m having some clutch slippage recently on my 94 22re manual trans 4x4 runner.

I did a new luk/aisin clutch flywheel kit new throwout bearing new rear main and new plate that rear main fits in about a year and a half ago. Oh yeah and a new slave cylinder.

Recently it starting slipping on big hills at high rpms. And also pulling off the line at lights in 1st gear. I parked on a hill tonight and in reverse it just keeps slipping and not holding on the hill like it should.

I’m afraid that the shaft the seal fits and should seal over is grooved and is causing the leak. I want to double check everything else that could be causing it before I start to think about pulling it apart.

Reason I think it’s this is the front main seal leaked for a few months and I just replaced it with thin seal that seats in different spot on shaft. No leaks and my engine is finally clean again. I figure if there’s a groove there there’s probably one on the back. Wish I had known this when I did the clutch but I never read anything about it until now.

So other possible causes. First time I noticed it slipping on hills I had topped it up before a long trip loaded with weight. I read that the half moon in back can leak and oil can get down between engine and trans.

Well those were definitely in need of replacing along with the valve cover gasket. There was oil back there too. I’m thinking that top off going up big hill probably juiced some oil out the back and down onto the clutch.

So I sorta hope this is the cause and I had hoped it might sort of burn off. But I’m getting some brake cleaner to squirt up in the clutch zone to hopefully clean it off the rest of the way.

I really don’t want to pull the trans again. It was a pita. But I will do if possible.

I’m thinking other two possible causes. Would be failing slave cylinder which seems less likely cause it’s new.

or trans seal is leaking. Had I known about this I would have done when I had it off.

or could a bad master cause this? I had a brake master go bad that wasn’t visibly leaking but it blew out inside. Brakes went to ˟˟˟˟ had to pump them to stop.

Any other possible causes?

 

If the master isn't properly adjusted, it can have pressure stuck in it. Holds the slave slightly pressing the fork, so the plates aren't together with full pressure of their springs. Easy enough to check. Open the bleeder valve on the slave cylinder, and if you get a squirt, it had pressure against it. Make sure the pedal is adjusted properly, and the master cylinder's plunger is aligned properly.

Not a huge help, but the best I can offer. I am NOT a clutch/transmission kinda guy at all.
Pat☺

 

Thanks for the input. I still haven't got it figured but there doesn’t appear to be anymore oil dripping from bell housing weep hole.

I’m thinking it was the rear valve cover moon dripping down the back of engine between the two

I’ve been noticing that the clutch master cylinder is quite squeaky. I had the wife pump the pedal and put a screw driver on the CMC and that’s directly where the noise is coming from.

I’m considering a rebuild or replace since it’s relatively cheap and easy and this is still the original master. And only clutch part that hasn’t been replaced yet.

If it is squeaking and leaking internally would that let the clutch slip?

 

Also no expert here, but slipping clutch either means A) your pressure plate cannot hold the clutch disc firmly to flywheel or B) pressure plate is fine, but disc is worn or oil soaked

Now, for A) perhaps Pat is right and your pedal is misadjusted and putting constant pressure on the pressure plate, I suppose this is possible but seems unlikely to me. Perhaps something is stopping your pivot arm from sliding the throwout bearing all the way back and relieving pressure on the pressure plate?

I would remove that little bellows rubber sleeve on the pivot arm and see if you can get a look inside there, maybe you can see if the pressure plate fingers are being released, also look for oil on the disc, unbolt the slave cyl from tranny and move that pivot arm back and forth and make sure it moves freely.

 

Nowadays, the whole CMC isn't much more expensive, if at all, than a rebuild kit. I would just replace the whole thing. Squeaking usually indicates either the seals getting old, or there's a mouse trapped in it. Personally, I would bet on the seals getting old, but hey, I've been wrong before.

Remember, adjust the clutch pedal properly once you've installed the new CMC. That's very important. It's not hard, but it's critical to the proper operation of the clutch's hydraulic system.

Good luck to you!
Pat☺