Has anyone tried putting it in a 94 LX transmission? I'm sitting at over 200k (somewhere over, just fixed the odometer) and shifts are getting pretty rough, especially 3rd and reverse. A Volkswagen friend of mine suggested GM Synchromesh, says the stuff is magical in a high mileage trans. Any thoughts?

 

Not much downside to trying a new fluid. You can always drain/replace if it does no good.

Once synchronizers are worn out, they don't get better. If your shifts are hard to engage, dragging clutch more likely the problem. If they shift OK but grind, the synchronizers are issue.

good luck

 

I've heard lots of good things about that. Like Tex says if you can't get into gear look for a dragging clutch.

But if you can easily push through the synchro & grind the gear, then try that stuff. I'd say the Synchromesh is a bit better than Honda MTF, which in turn is a lot better than the 10w-30 engine oil that your owners manual calls for.

Look for Pennzoil Synchromesh in parts stores. Same stuff & it might be slightly cheaper than GM dealer parts counter.

 

Could you give me a quick way to check if my clutch is, as you say, dragging? For instance, if the idle drops mildly at idle in neutral? I mean, there are a host of other problems that could be causing that... Throttle is binding at near idle position, tends to stick closed. Lost one injector for a few minutes yesterday, resolved itself following a couple of hard rev/restarts. EGR ports were horrifyingly clogged until last week. Valves are making an odd noise on a cold start, goes away when idle drops. Disregarding that, how do you adjust a hydraulic clutch pedal?

 

As I said, are shifts hard (hard to shift into next gear, holds at gate but won't engage) or does car shift easily but grind on engagement?

A dragging clutch usually results in hard shifts and change in engagement position (engagement occurs earlier or nearer floor).

First above is key to problem and you didn't say which is the case.

You don't adjust a hydraulic clutch.

good luck

 

You don't adjust a hydraulic clutch pedal. The master cylinder has to be at the proper position when you are NOT pressing the pedal, so the vent port is open. That's how it adjusts itself. You CAN mess it up by trying to "customize" & raising or lowering the pedal.

You can check for a dragging clutch a couple ways; here's one way:
Engine running, transmission in neutral, clutch engaged (that means pedal NOT pushed down).

Press down the clutch pedal and after a second or 2 shift into 1st gear. Is it difficult to shift into gear? Compare with the same procedure when the engine is NOT running.

A dragging clutch will make it difficult to put into gear when the engine is running. But it's easy when the engine is not running. Normal to be a little difference, but I guess the trick is knowing what's "excessive".

Another way is to lift the front of the car. Support it REAL SOLID so you can start & run the engine; chock the rear wheels. Disengage the clutch (press down the pedal) and shift into first. While holding the clutch pedal down, do the front wheels begin to spin?

If the clutch drags, then the question is whether it's the fault of the clutch itself or the hydraulic system. More things to check for that...

 

Any idea where the nut on the shaft for the clutch pedal should be? My brain suggests to me that the same idea I had and just asked you about (attempting to adjust a hydraulic clutch) was attempted by the previous owner. Which would not surprise me given the configuration of a few other things on this car. (For example, the TCS lead is wired directly to the stereo)
Also yes, hard shifts. Not grinding, but difficulty getting the lever into gear.

 

This problem won't be cured w/ different trans lube. It will likely require a new clutch.

good luck

 

Well, if the dragging clutch is caused by hydraulic problems, then the actual clutch might be OK. If you're lucky...

Find the clutch slave cylinder & throw-out lever, between the engine & radiator. Have someone pump the clutch pedal a few times then hold it down. While pumping, the leverl should move back & forth about 12mm. When the pedal is being held down for a couple minutes, the lever should NOT slowly move back & compress the slave piston. Try that & let us know.

Then after doing that, with the clutch pedal NOT pressed down; push the lever towards the clutch slave cyliner. You should be able to compress the slave piston back into the cylinder a little ways. When you let go, it should slowly spring back out. That will verify the master cylinder is able to compensate with it's own internal vent.