Transmission Rebuild
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Joined: Oct 2004
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From: Bakersfield, CA, for now...
Matt: Repair cost depends on usage + mileage. If you can give me both, and describe any current difficulty that the trans has I can give you a pretty close guesstimate.
Pete
Pete
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Burning Brakes
Joined: Nov 2003
Posts: 966
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From: Mahopac, NY
Pete,
I don't know the mileage. I'll have to find that out.
I think what he last told me was that the transmission was engaging two gears at the same time. (If that's even possible.) But he was having a lot of shifting problems getting the car into gear. The problem became worse and at this point I'm not sure if the car moves anymore.
I don't know the mileage. I'll have to find that out.
I think what he last told me was that the transmission was engaging two gears at the same time. (If that's even possible.) But he was having a lot of shifting problems getting the car into gear. The problem became worse and at this point I'm not sure if the car moves anymore.
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Joined: Oct 2004
Posts: 20,607
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From: Bakersfield, CA, for now...
Two gears at once is almost always due to an incorrect shift fork adjustment internally. If you have repair records it would be nice to see if/when the trans was apart, and why. The condition can be fixed by removing the plate from the bottom of the trans and applying pressure to the shift forks. Unfortunately I've seen the problem repeat. It seems that a bad habit by the driver can contribute. If the car is being backed up, especially with the steering applied (as though you are backing into the street from a driveway), and the car is removed quickly from reverse, while the car is still rolling backward, and put into first the problem can occur. Of course, the best way to avoid that scenario is to bring the car to a full stop, in reverse, with the front wheels straight, then remove the car from R and put it into 1st. That technique does help. Get more info if possible.
Pete
Pete
Thread Starter
Burning Brakes
Joined: Nov 2003
Posts: 966
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From: Mahopac, NY
Pete,
Just spoke to him. You are right on target with your analysis.
The problem occurs when going from first to reverse or vice versa. He says if you are going slow and shift quickly is when it usually happens. When it does lock in two gears he told me he usually lets the car sit for a while and eventually it somehow corrects itself.
The tranny has 100,000 miles on it. I doubt he would know the last time it was opened up (if ever).
On top of that, he tells me his syncros are shot on first gear. He has to double clutch to get the car in first.
Just spoke to him. You are right on target with your analysis.
The problem occurs when going from first to reverse or vice versa. He says if you are going slow and shift quickly is when it usually happens. When it does lock in two gears he told me he usually lets the car sit for a while and eventually it somehow corrects itself.
The tranny has 100,000 miles on it. I doubt he would know the last time it was opened up (if ever).
On top of that, he tells me his syncros are shot on first gear. He has to double clutch to get the car in first.
Burning Brakes
Joined: Dec 2003
Posts: 814
Likes: 1
From: Vah Beach
Matt,
As a reference point, I just had my trans rebuilt by Mark Finley at REZOOM in Blountville, TN, near Bristol. My final cost was about $3000, and that is with me delivering the transmission to him and picking it up. So your friend may need to add the cost of engine/trans drop and install. Also add cost of clutch, pressure plate, and trow-out bearing.
My rebuild included all new synchros, a couple of sliders, a couple of dogteeth, a pinion shaft bearing, and seals and gaskets. Parts were nearly $2000.
Don
As a reference point, I just had my trans rebuilt by Mark Finley at REZOOM in Blountville, TN, near Bristol. My final cost was about $3000, and that is with me delivering the transmission to him and picking it up. So your friend may need to add the cost of engine/trans drop and install. Also add cost of clutch, pressure plate, and trow-out bearing.
My rebuild included all new synchros, a couple of sliders, a couple of dogteeth, a pinion shaft bearing, and seals and gaskets. Parts were nearly $2000.
Don
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From: Bakersfield, CA, for now...
Matt: Don's post is good, the repair cost grows quickly when parts are needed. I have a hunch that your friend's trans is going to need similar pieces as Don's did. Just don't try a shortcut and use new synchro rings with old sliders, that would be a disaster. If the 915 is in an SC it's a perfect time to do what's necessary to the clutch, and definitely replace the thermostat o-ring, oil pressure switch, throttle lever (aka bell crank) bushings on top of the engine. In other words, fix all the stuff that only takes a few minutes with the engine out that are a real pain to do otherwise. Labor rates are higher now than when I sold the shop, so figure about three hours to do the R&I, an hour to do the clutch, an hour to do the little things mentioned above (if the car's an SC consideration should also be given to the airbox, injector seals, etc.), and whatever it takes to repair the trans, about eight hours is typical. Bearing replacement is strictly up to the rebuilder, I like to do them on units with more than 200K miles, but it's usually not necessary at 100K miles.
Pete
Pete
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From: NATICK MASS.
We do 915 gearbox on a very regular basis and the cost can vary widely. If the syncros are worn but the other bits are not yet compromised, the total time spent can be 6-8 hours with the gearbox on the bench. We also always check the ring and pinion settings for pre-load, depth and wear pattern. The other parts that need to be carefully inspected are the tensioning plates that hold the input and pinion shafts down. The average cost for the job runs $1500-2500. I also strongly recommend using syncros directly form Porsche, many rebuilders don't and the gearbox will not work as smoothly without them.
Good luck, Jerry
Good luck, Jerry
