Whining After 5th Gear Swap

[dvancura2]

I've got a 03 Jetta 5 speed. I recently picked up a .658 5th gear swap and installed it. Got new fluid in, put back together, and took it out for a drive. I get the noise heard in the video. Everything shifts fine, everything feels smooth, ran through all the gears. 4th gear is probably the quietest, 3rd gear is the loudest. One thing I did not do was get an exact torque on the end bolts for the gears, but had gotten them pressed on the shaft completely. Has anyone experienced the same or has any ideas? Theres no break in period on these gears until they quiet up? They are cascade german gears.

03 Jetta Noise

Noise I hear in the transmission after doing a 0.658 5th gear swap/

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[JETaah]

Just a shot here but, I had run into an issue a long time ago doing a similar 5th gear conversion where the Belleville spring washer that was fitted to the face of the small gear was now running into the edge of the larger gear of the new 5th gear set.
If this is the case then it may leave marks on the edge of the washer.

 

[dvancura2]

I really should have taken a picture after I had everything in there to reference... What did you do to fix it? I ended up putting on a total of probably 100 miles and the sound is starting to go away, I can faintly hear it in 2nd, and sometimes in 3rd. If it is the washer rubbing, sounds like it maybe wore in, which means some metal got relocated and is probably now in the fluid. Wish MT90 was a little cheaper, but I guess two more qt is cheaper than a transmission. I don't think it makes much sense though that it only makes the sound under acceleration. You would think it would make it all the time while driving, unless the torque while accelerating shifts the shaft just enough to touch the gear to the washer.

 

[JETaah]

Just pop the 5th gear cover off and have a look at the edge of the washer. It is bound to show a bit of shine if it in deed has been in contact.
What I did was to stick it on the lathe and just skim the perimeter off a bit. Might be able to do the same by fashioning an arbor to stick it in a drill press and take a file to the edge.
However, you get the idea, right?
I believe that there are different washers for the different ratio of gear sets. and while it was very close the couple that did this for me happened to have a slight interference.

Making intermittent contact may be due to some thrust clearances getting a bit larger than they used to be.. Don't know. Could be something altogether different. But if the spring washer overlaps the small gears teeth at all then there is a chance that this is the cause by hook or crook.

 

[dvancura2]

10 points to Gryffindor. Got my oil in so I could pull things and get it back together. Sure enough...we were trying to make new teeth out of the washer. I'm surprised because I did a fair amount of research before doing this, and I don't think I ever read anywhere that this washer may need modified. The kit I bought did not come with it and I had to buy a new one separately, so maybe the kits with the washer included don't have this problem.

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• dvancura2
• Mar 27, 2023

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• dvancura2
• Mar 27, 2023

I ended up using a homemade "lathe", chucked the gear bolt up into my cordless drill with a roll of electrical tape as the spacer to hold the washer, zip tied the trigger to get it spinning at a constant speed, and took an angle grinder to the side to grind it down. Worked like a charm. I took it down until I couldn't see the teeth marks, and then just a tad more. Got it all back together, and she is as quiet as can be. My fault for failing to look closely once all back together. I hope that this will help anyone else who might run into my situation before putting a 0.658 5th gear in their Jetta. Thanks again JETaah!

 

[IndigoBlueWagon]

The .658 gearset requires a smaller washer on the small gear, as you have now discovered. PN is 02Z311324.

 

[csstevej]

WELL DAMN….. congrats on the find and fix.