Downshifting in higher gears has become almost impossible.
#1
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Yesterday, I was driving over 100 mph for much of the way to Vegas in 6th gear, way out in the desert. When it came time to downshift, I couldn't find 5th at all. I had to coast in neutral, blip the throttle and got it into 4th, which felt rough. Shifting back up into 5th and 6th was like butter. I drove around in Vegas traffic for a while and all was fine at slower speeds and I never got up to 5th gear. Driving home today, same thing happened. I discovered that very quick double clutching would get into the next lower gear, but it never felt quite right and once or twice I heard that terrible grinding noise, while trying to push it into gear. WTF is this? How is it so sudden? All was fine last time I drove it.
I last changed my tranny fluid a year and 6k miles ago, Mobil 1 75/90. I have the factory short shift kit. How can it be bad synchros if upshifting is always fine, but downshifting is always bad? I removed the rubber shift coupler plate about two years ago and replaced it with a chunk of poly from a cutting board. Seems to me, if that had gone bad or melted, I'd have had bigger, more consistent problems. Anyone ever have this happen?
I last changed my tranny fluid a year and 6k miles ago, Mobil 1 75/90. I have the factory short shift kit. How can it be bad synchros if upshifting is always fine, but downshifting is always bad? I removed the rubber shift coupler plate about two years ago and replaced it with a chunk of poly from a cutting board. Seems to me, if that had gone bad or melted, I'd have had bigger, more consistent problems. Anyone ever have this happen?
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They're the billet aluminum solid kind, have about five years and 30k miles on them. I am suspecting them now too, as the car feels like I'm driving in very high winds when at speed. I will take a closer look with a jack and ramps today. Too bad Wevos are out of stock. I hear the Boxster tranny mounts will fit 993 motors. Is that true?
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Yes, I looked at that. Just put her on ramps and used a floor jack at the case seam to raise it some more. I didn't see any flexing or obvious movement around the mounts or the carrier. I may pull all that stuff off just to inspect it more closely anyway. Looks like a bit of a headache to get it all out and I surely don't want to reinstall it before I get the Rennline reinforcement kit or new motor mounts. Rennline is saying mid-November, which is probably when I'm moving. It'd be a huge problem to make my car immobile and then not have the parts arrive in time to move it to the new place. Luckily, I have a lot of garage space now.
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Got the driver's side motor mount out and it looks new. Hardware could use replacing, but the mount is in fine shape. I can't see any damage to the carrier either. I poked around the shift linkage underneath the car and it's a tad loose, but I can't imagine it causing all these problems.
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#8
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Clutch is RS/LFW and about four years old. Slave is same age and I flush it completely once a year. I'm pretty sure that's not it, or else I'd be having problems in other gears too and at lower speeds, no?
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As your gearbox gets to really humming, 100 MPH etc, the gears are forced to slow from a greater speed when you downshift. Your issue is in the gearbox in all probability, and most likely just needs to be rebuilt.
I would be happy to talk to you about this in more detail if you would like.
Warmest Regards, and happy to help,
Erik Johnson
GBox Sales Manager
(303) 440-8899 work
(303) 895-4828 cell
I would be happy to talk to you about this in more detail if you would like.
Warmest Regards, and happy to help,
Erik Johnson
GBox Sales Manager
(303) 440-8899 work
(303) 895-4828 cell
#10
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As your gearbox gets to really humming, 100 MPH etc, the gears are forced to slow from a greater speed when you downshift. Your issue is in the gearbox in all probability, and most likely just needs to be rebuilt.
I would be happy to talk to you about this in more detail if you would like.
Warmest Regards, and happy to help,
Erik Johnson
GBox Sales Manager
(303) 440-8899 work
(303) 895-4828 cell
I would be happy to talk to you about this in more detail if you would like.
Warmest Regards, and happy to help,
Erik Johnson
GBox Sales Manager
(303) 440-8899 work
(303) 895-4828 cell
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I don't downshift at high speed. I downshift when my revs get below 3k and I need some more power. Sorry, but I'm pretty far from being ready to call this a necessary rebuild. There were never any problems before Sat. No funny noises, no hard shifting. I'm gonna do some more investigating. If it really needs a rebuild, I'll do it after Xmas when I've moved into my new house and gotten my garage all set up.