5 speed.

[Chainsaw39]

I have an 84 928 with a 5 spd. I have corrected a lot of problems over the last week or so since joining and today I took the 928 for it's first ride longer than around the block. I went for about a 6mile round trip ride down the interstate. When I left the house in 1st gear there was a loud thumping noise coming from the trans axle ( seemed loudest in the front section of the trans axle) went ahead and took the ride using 2nd through 5th there is the slightest noise in 2nd (I have to lift the shift lever boot to hear it. Anyway after the 6 miles on the interstate I used 1st gear again and the thump was hardly audible? I replaced the trans-axle oil last week with synthetic. Anyone had this type of issue. Also how involved are the trans-axle repairs (from a shade tree mechanics point of reference) I have rebuilt a ford 4spd or 2 and a nissan 5 spd. Should I attempt to tackle the Porsche 5 spd or look for a good used one? Sorry about the length of the post I have been known to ramble.

[Danglerb]

You will need a few special tools, giant snap ring pliers, and maybe need to have this or that pressed on or off, but there are some good write ups for fixing a transmission on a early car. That caveat that I would add though is that despite having experts show me everything step by step, identification of types of wear on some parts is NOT easy, and shot gunning a lot of parts is expensive.

That said with a 5 spd, its very hard to be sure of where a problem is located, clutch, torque tube, or transmission.

I would not be driving it until the source of the clunk is identified.

[Chainsaw39]

Thanks Dan I am assuming that there are u-joints or some type of cv joint in the torque tube because all i see hooked to the trans is a fixed tube (torque tube?) the shaft must ride inside the tube?

[MPDano]

Originally Posted by Chainsaw39

Thanks Dan I am assuming that there are u-joints or some type of cv joint in the torque tube because all i see hooked to the trans is a fixed tube (torque tube?) the shaft must ride inside the tube?

Search is your friend here on Pelican. Pics are of Glerbs old TT.

Torque Tube Rebuild Begins

[Danglerb]

Because the TT is hollow, makes it VERY hard to tell if a noise is from the front or the back, ie clutch or transmission or the TT itself.

TT has two or three bearings inside that can wear out or move. No flex, its rigid engine to differential which is how it does its magic, no torque bias on the rear wheels when accelerating. On a drive shaft car with an engine producing 300 ft/lbs of torque, same torque (twist) applies to the rear end pushing one wheel down an extra 100 lbs or so and lifting the other side by the same amount.