Differential interchageability

waynehoc · Post by **waynehoc** » Tue Oct 11, 2005 8:18 am

Hi - new member - great site which I found doing a search for an emissions problem with my Tercel Wagon -'87 FWD 5-Spd with 246k kilometers on the clock. This is a Canadian car, as I'm near Vancouver B.C.

Have a question re interchangeability of the differential between FWD 5-Spd and 4WD 6-Spd. Have searched the forum and checked the downloadable pdf of the FSM and it is obvious that the transmissions are not interchangeable, but it appears that the differential portion is, as the manual does not differentiate between the differential for either. Can anyone confirm that they are indeed interchangeable (or not)?

Reason is that I have a clunk in the drivetrain if I'm not careful when letting the clutch out when changing gears. CV joints are good and clutch just recently done (complete job - clutch, pressure plate, t.o. bearing, machined flywheel). Have raised the car and checked and there is noiceable slop internally in the differential when rotating the axles back and forth by hand on either the driver or passenger sides. So I'm convinced the must be excessive gear lash internally.

I have a chance to get a parts car for a reasonable price, but its a 4WD SR5 6-Spd, still driveable. Have taken it for a spin and the trans and differential feel fairly tight and easy to shift - the original complete transaxle/rear diff were changed a little over a year ago when the original trans died. Whats in the (parts) car now came from and unknown vintage 4WD in Alberta.

If the diffs are interchangeable I would buy it and strip off what I want keep and make the rest available. Should be a good transmission for someone, at the very least.

Please let me know what you guys think of the diff interchangeability between the FWD (my car) and the 4WD (potential parts car). Anyone have any idea what a good transmission might be worth?

Thanks

waynehoc · Post by **waynehoc** » Tue Oct 11, 2005 8:20 am

Should also add that I have very carefully checked the engine mounts and the trans mount, and I'm convinced that they are fine. Also aware from other posts about the different drive ratios for 83-84's vs 85-87's(88).

Wayne

3A-C Power · Post by **3A-C Power** » Tue Oct 11, 2005 4:31 pm

The differential is the same but the ring and pinion gears are different in the 4WD. If it comes from an 85 or later 4WD then your gears will be lower. You may find the ring and pinion are still good and you can use them again. You can take a look at the diff by taking the front cover off to determine what gears are worn out.

waynehoc · Post by **waynehoc** » Tue Oct 11, 2005 9:44 pm

Thanks 3A-C Power, I'll have a look when time and weather permits.