Clutch and/or transmission

YouTube · Post by **Mikewire** » Nov Mon 19, 2007 10:59 am

So anyone with MKIV experience...

Bought the Jetta with 63k in 2002.

My transmission has always been kinda cranky...It's sometimes hard to shift into 1st, I get the 2nd gear grind and sometimes if I downshift into 3rd the syncro will sync correctly and I grind the gear.

I changed gear oil to a Delo 80W-90...maybe not the correct stuff to run?

But lately it's really been a pain in the ass, and sometimes I can't even get into first without rocking the car or taking off the e-brake to release the pressure on the wheels. When it's cold, from 1st gear I usually skip 2nd gear and go right into 3rd because 2nd grinds until I warm up, and when I am in 1st going slow, it almost sounds like the car is still slightly in gear even when I have the clutch depressed.

My clutch doesn't slip, but my clutch engages with less than 1" from the full release position, and I notice it chatters a bit - but no slippage. It feels notchy, but I also have the TT shift linkage.

I plan on ordering stage1 dogbone bushings from BFI...

So - two questions:

Should I change gear oil to a different kind? Any recommendations?

Could my clutch be going out? Should I replace it before it starts slipping?

To refresh - I have a 2.0 AEG stock, with the 02J transmission - 120K on the odo clock.

Post by **RuS4ty** » Nov Mon 19, 2007 12:04 pm

syncros could going...

Post by **ValveFloat** » Nov Mon 19, 2007 12:44 pm

When it's cold, from 1st gear I usually skip 2nd gear and go right into 3rd because 2nd grinds until I warm up

Sounds like synchros

when I am in 1st going slow, it almost sounds like the car is still slightly in gear even when I have the clutch depressed.

Sounds like the clutch isn't completely releasing.

Based on what you said, I think you have two problems, and the clutch issue is aggravating the synchro issue. The clutch not releasing when the pedal is on the mat could be a couple things, but from what I have read about mk4s, the first thing to check is the slave cylinder, and I would get on it before you do more damage to the dogs. Every time you grind you are wearing the dogs, and they are not as cheap as synchros.

Post by **Custom VW** » Nov Mon 19, 2007 2:01 pm

Rebuilt a 02j last week that had three broken syncro;s in it. Never seen them break like this before. broke bad enough to break the shift hub. Dealership has an updated version of the whole 1st and 2nd gear shift assembly for about $750.

on the pedal issue, I agree that you should check for hangups in the hydrualic sytem.....make sure there is fuid above the minimum in the resevour. I have seen two clutch's come in that were not slipping, but hanging up. evidently the dust and debri can build up around the clutch and actually drag the clutch enough to grind gears. both of these were aftermarket clutch's on stock flywheels.

YouTube · Post by **Mikewire** » Nov Mon 19, 2007 3:57 pm

Thanks guys - I'm definitely going to check out the hydro system. I don't suspect anything is broken, but with 120k, things are worn a bit.

I think the clutch is wearing thin, but a mojority of my driving is highway, so I may wait to get that done.

However, it's way past time to replace and bleed the brake system, so I will bleed out the system with new fluid and see if that helps my clutch issues as well. I have heard of ATE super blue DOT3 - it's supposed to be pretty good - any thoughts?

I will also go with a different gear oil - any recommendations on that?

CustomVW - is that debris build up from clutch material? Or is it mud etc? And how would I know if I had broken syncros? At $750 I may be better off upgrading to a slightly used 02M...? If it would bolt up that is...

Edit - I should add that I did adjust my shift linkage and that helped a bit, but I still have some tough shifts. I have driven other Jettas that shift really smooth, and compared to them mine feels really notchy. Would it help to pull the inside shift mech and lube that up? Maybe also on the transmissions side? Being cable driven I could see how the cables may get sticky after a while...esp being in the engine bay.

Post by **ValveFloat** » Nov Mon 19, 2007 4:06 pm

I have heard that Super blue is bad for the clutch slave cylinder, but I don't know why. I have had good luck with ATE Typ200, which is essentially Super blue without the blue dye.

Post by **Roadhog** » Nov Mon 19, 2007 5:48 pm

Super blue is just dot5.1 or something with dye.

Mike, Give the GM Syncromesh a try, I bet it doesn't grind anymore.

Post by **ValveFloat** » Nov Mon 19, 2007 5:52 pm

Roadhog wrote:Super blue is just dot5.1 or something with dye.

Super blue is DOT 4, but has good dry and wet boiling points.

I am pretty sure its ok for the brake system since I ran it last summer, but I have read that it is bad for the clutch slave cylinder, I really don't know why. Typ200 has the same boiling temps though and no dye, so should be fine.

I have a fresh can of ATE DOT 4 if you want it Mike. A friend gave it to me thinking it was Typ200, but the boiling temps aren't quite high enough for me.

YouTube · Post by **Mikewire** » Nov Tue 20, 2007 9:56 am

ValveFloat wrote:
Roadhog wrote:Super blue is just dot5.1 or something with dye.
Super blue is DOT 4, but has good dry and wet boiling points.

I am pretty sure its ok for the brake system since I ran it last summer, but I have read that it is bad for the clutch slave cylinder, I really don't know why. Typ200 has the same boiling temps though and no dye, so should be fine.

I have a fresh can of ATE DOT 4 if you want it Mike. A friend gave it to me thinking it was Typ200, but the boiling temps aren't quite high enough for me.

Thank Joe...sure, I'll give it a try - I can't imagine why it would be bad for the clutch cylinder. Let me know what you want for it.

I picked up some Pennzoil Syncromesh last night from the GM dealer so I will give that a try in the grinder.

Post by **Custom VW** » Nov Sun 25, 2007 1:31 am

Debri is from clutch material, and in one case yesterday...a tire store mess up on a tranny swap left a plug in the bell housing (elctrical plug).