Tko600 Warning!!!!

[craigayl]

Yes Anthony "the same failure"

Note that on the forward side of the main shaft gear the teeth are copletely gone and on the rear side the teeth are full as if they were not in contact with the countershaft gear. The oposite is true of the countershaft gear. A more indepth investigation is necessary. If these gears were properly aligned, the teeth should have come off more evenly.

Craig

[eschaider]

Yet another late comer ...

It took a long time to read all the posts but things become increasingly apparent the farther you read. Anthony, Scott and Craigayl (the gang) got it right! So did Fordfan. For what ever reason Fordfan suspected he would receive poor warranty treatment and tried to position himself for the best possible. He bent the truth, to that end.

Keisler either doesn't understand how these boxes work or intentionally tried to sidestep their warranty obligations. I don't believe any reputable Tremec rep would have come to the conclusions that the Keisler folks have stated he did. I also don’t believe that Keisler doesn’t know how these boxes work!

As several of the ‘gang’ pointed out the gears are constant mesh gears if a shift is missed then the synchro dog teeth on the gear take the beating not the gear teeth! Craigayl tagged the most probable source of failure. The driving and driven gears are misaligned! If you loose 20% of the tooth face contact area, through misalignment, you have only 80% of the original design torque capacity left.

When you look at the picture there is no two ways about it the driving and driven gears are misaligned. As a commercial rebuilder of these boxes that should have been a red flag for Keisler, unless of course they have a reassembly problem that produces the misalignment. If the gears in Fordfan’s box are not misaligned then we are dealing with Scott’s analysis which is an ultimate strength failure caused by the driving and driven gears moving apart under power.

Tremec could shed considerable light on this with their finite element analysis they performed on the box during the design phase. That would quickly tell us if the third gear gearset was/could spread the case enough to induce the tooth failure. Judging from the pictures though I really believe the box was improperly assembled. The driving and driven gears for third were misaligned and the failure was directly attributable to less than complete gear tooth face contact reducing the torque capacity of the unit.

The real question is why Keisler tried to cover up and place the blame on the user. Experienced transmission shops would quickly identify the misalignment as the source of the failure. Why didn’t Keisler?

I think this bodes poorly for the type of treatment the rest of us are likely to get if something like this happens to our box. I also think it may be worth a little effort to take a look inside our own units to see if we have a similar misalignment in the third gear gearset. It will be quite telling if the misalignments exist and the reseller does not want to correct the problem prior to component failure!

It would also be quite telling if the Tremecs that had not been opened by the reseller did not have this problem. Maybe it’s time to take a quick look at our transmissions before it’s too late. If your tunnel cover can be removed it makes the job much easier than removing the whole box (or engine and box).

Ed