TTVA problems, or maybe not

[buzzinghalfdozen24]

Hi guys,

Looking for some help on my transmission. The engine, trans, etc works perfect all the time, expect for one down shifting and shuttle shifting issue. Longgg story short; built trans myself and it performed flawless for two years. After about two years I started having a weird shifting problem. The trans would flutter between 1 and 2 when cold. All the time, every time. When I would drive it around to work and such, downshifts from 2 to 1 would be abrupt. About 10mph the truck would just clunk and drop a gear.

As a side note, at this time I performed a full transmission service. Oil, filter, bands adjust and inspect. No change in performace.

After calling a few recommended trans specialists (Goerend), we were convinced the TTVA was not taking calibrations. We were able to remove the old TTVA from the trans and the problem went away, replace it back in place, problem returned. Georend was sure TTVA was bad. I just swapped in a new one. I did the whole key on for 30 seconds calibration and it still does it. What's weird is that once I've driven it around for a while and everything is up to temp, it doesn't do this problem.

Any ideas, I'm getting pretty desperate and don't want to just start guessing

 

[cerberusiam]

Take the TS box off and the problem will likely disappear. What gov solenoid did you use in the build? The combination of the shift enhancer, shift kit, and gov solenoid will sometimes create other issues. I have removed the shft enhancer, used the GM style solenoid, and advanced the TTVA motor one tooth in the gear asembly for better results. Got rid of the abrupt downshift to 1st anyway, not that it was bad just different because of the advanced TTVA postion.

 

[buzzinghalfdozen24]

Interesting. I thought of that, but wasn't sure. I had ran the ts box for 2-3 years with no issues and the problem just randomly started happening. But honestly. I never used the ts box settings anyway. When I did my trans rebuild, I left off my wave springs for firmer shifts. That's fine and dandy, but then with the ts box added too, it was too much. shifts were harsher than I wanted. So I always had it turned down all the way. The ts is a "splice-in" not a plug and play, so removing it is a little more of a chore. But I like you thinking.

Explain the advancing the ttva one tooth option, please. Not sure what that gains me. And I'm assuming just drop the pan and adjust it? I've heard about this but never read up on it.

 

[cerberusiam]

There is a metal cover with tangss on the bottom of the TTVA if pry them loose and pop the cover off you can see the shaft for the actual motor and the gear that actually turns the TV shaft. With the TTVA assembly upside down you pop the gear up and out and advance it one tooth to advance your intial TV pressure. That wil take it from 0 psi at rest to 5-7 psi at rest. That will normally cure the shuttle shift at light throttle and extend the shift points a couple mph. That is essentially what a shift enhancer does, advances the motor on a different curve than stock and starts at a different place.

Remove the TTVA
Remove lower cover - Metal cover that is clamped with metal tangs.
Remove cover carefully so the gears do not fall out.
If you turn the shaft counterclockwise, looking at the actuator up side down, it can result in codes 1751 and 1754.
Adjusted the shaft one tooth CLOCKWISE.

 

[buzzinghalfdozen24]

Ok thanks. I'm checking all that right now. So I guess my biggest question, Is the shift enhancers actually needed after completing a transgo shift kit?

 

[cerberusiam]

With the shift kit, the GM style solenoid, and advancing the TTVA gear I found it wasn't needed so I pullled mine off. As long as don't remove too much of the TQ management or slow it down with the Smarty POD it works fine. Will still get into shuttle shift if the throttle is too light during driving but no where near as bad as stock.

 

[Prairie Dog]

Is shuttle shift detrimental to the life of the trans?

 

[cerberusiam]

With the TQ these engines make, it is not the best thing to have on a constant basis.

 

[Prairie Dog]

Thanks Cerb.
I happened to be riding in my buddy's 06 today and experienced it for the first time.
I printed out your instructions for him - he just got done installing the "bullet" and grinding the rooster. I like keeping him busy working on his auto while I tease him about my hand shaker. :-laf

As much as shuttle shift happens, some directions with pics would make a great sticky.

Scott