December 2008 i broke my stock transmission (broken output shaft) so i bought a built transmission from a local builder. well, today that transmission broke on me, it too seems like the output shaft broke. the truck will not move in any gear, will not roll backwards even in neutral and the driveshaft is stuck on the output shaft so im guessing that the splines are twisted and holding the driveshaft on. so i have now broken 2 transmissions in less than 15 months with a stock engine, bolt ons and tune only.

this sucks. i guess whatever trans i buy next is going to have a billet output shaft no matter what. any suggestions on who i should have build my next one?

 

Who tuned it? If you're breaking output shafts, you're shift pressures are likely set too high

 

I can agree with that. How hard does it shift?. No slamming the gears right?

 

That sucks to hear man. But somethings not right with a "built" trans that breaks behind a stock engine.

 

Virgil tuned it. we had the line pressure set pretty conservatively because of the stock transmission, this transmission has vacuum regulators though so there was no changing the pressures. it broke both times shifting into second gear, which at WOT was a VERY firm shift but i dont think it was enough to break anything especially with street tires

 

I have seen way stock vehicles break parts just as what has happened in your case here. A few things come to mind when I hear about issues like this.

How is the vehicle treated?

Are you doing manual downshifts at high speeds?

How hard does the trans shift?

Are you going WOT every time this thing leaves the house?

Are you spinning your tires doing John Force burnouts until it grabs?

How was the trans set up? End play and clutch/band tolerances?

When the trans broke how was the shift?

Is there a lot of slop in the drive line?

The list could go on but I think you see my point here. I guaranty you more than one of the above can be addressed. Like anything else performance related, when you have a failure you need to improve on the build in order to keep from having the same issue time and time again.

I find in some cases if you are stupidly abusing something, it is not a matter of if but a matter of when it will break. In the OP's case it took 1-2 years to have the exact same failure. I have seen this happen in much less than that!

Good luck with getting your truck back up and running. If there is something we can do for you, please feel free to give us a call to over your next build. Vince

 

How is the vehicle treated? it is my dd. yes i do beat on it from time to time but for the most part i drive pretty sensibly

Are you doing manual downshifts at high speeds? i have never done this

How hard does the trans shift? i wouldnt say it shifted hard but more firm, you could tell there was no slipping between shifts

Are you going WOT every time this thing leaves the house? definitely not

Are you spinning your tires doing John Force burnouts until it grabs? i have only done one good burnout with this trans in the truck and that was about 3 weeks ago on the street

How was the trans set up? End play and clutch/band tolerances? im not sure on this one. the builder would know i guess and i went with him because i heard he had a good rep building race transmissions

When the trans broke how was the shift? the truck didnt jump or anything, no pop or bang, went through first gear and then seemed like it went into neutral

Is there a lot of slop in the drive line? not much at all. the gears are set up pretty tight and i have a yank tt2600 so it is a pretty tight converter too

 

Bring it to me, I'll fix it.

 

^^^agreed...builds a badass trans

 

Speaking of that, how is yours doing