Transmission hard shift

[JIM KELLER]

I notice my transmission shifts with a hard hit going into 4th gear. Same thing downshifting into 4th. The problem is enhanced if the Jake Brake is on while going through the downshifting process. All other shifts are fine and 4th is tolerable as long as I remember to pull my foot out of it on the upshifts and turn off the Jake before it goes into 4th on the downshifts. Is this anything a Reader could find ?

[Jon Wehrenberg]

I had the same characteristics. When mine was diagnosed prior to re-teaching it was found two of the clutches were excessively worn and that was creating the problem.

So I swallowed hard and opted for a 2008 spec factory rebuild. It was very close in price to what rebuilding mine would have been.

The new one took a few trips to "learn", but the shifts are barely noticeable now. It only cost $13,000 to smooth out those shifts.

[JIM KELLER]

I had the same characteristics. When mine was diagnosed prior to re-teaching it was found two of the clutches were excessively worn and that was creating the problem.

So I swallowed hard and opted for a 2008 spec factory rebuild. It was very close in price to what rebuilding mine would have been.

The new one took a few trips to "learn", but the shifts are barely noticeable now. It only cost $13,000 to smooth out those shifts.

THATS JUST LOVELY !

[rfoster]

Last year my tranny was shifting hard up and down in 4th, I picked up a code that the speed sensor was going bad or had a bad connection. I had Covington Diesel (the Allison/Detroit Bank and Trust in this area) install a new speed sensor and then changed the two small filters in the tranny for about 150.00 lew bucks. This was about a year ago and I am still burning fuel. If I have used the retarder, it will still shift hard.

Check for codes before spending big bucks.

[JIM KELLER]

Last year my tranny was shifting hard up and down in 4th, I picked up a code that the speed sensor was going bad or had a bad connection. I had Covington Diesel (the Allison/Detroit Bank and Trust in this area) install a new speed sensor and then changed the two small filters in the tranny for about 150.00 lew bucks. This was about a year ago and I am still burning fuel. If I have used the retarder, it will still shift hard.

Check for codes before spending big bucks.

Thanks Roger. Hopefully Jon will offer to read my codes sometime at Sevierville.

[Jon Wehrenberg]

I don't know if the software I have will access your codes. But as long as you are going to use my X12 you might as well use my reader. I'll trade for some catalogs.

[JIM KELLER]

I don't know if the software I have will access your codes. But as long as you are going to use my X12 you might as well use my reader. I'll trade for some catalogs.

O.K. Its a deal.