3rd gear slipping

[dwax]

after the new power of my twins, my transmission has been acting funny in 3rd. It feels like it never catches good and slips all the way through 3rd until the converter locks or hits 4th. It doesnt do it as bad from a 2nd gear punch on the road. but during a race, it shifts firm from 1st to 2nd, then weak 3rd shift and does not pull hard until it shifts gears again. It acts the same in tow/haul. and is worse with my tranny temp at 190 than at 120. I have the c1-c4 alto clutch packs, transgo, and precision T.C.. Could a co-pilot help me out or is it more likely my tranny isn built right?

 

[sparepartsracing]

i dont have a built tranny or know alot but have you relearned the tranny after the twins?

 

[dwax]

yep. i did that twice

 

[8100 Power]

Who built it?

 

[sparepartsracing]

try changing the fluids and maybe you burned up c3? how many miles on the tranny

 

[DuramaxPowered]

Thats how my truck felt when the C3 clutches were wasted.

 

[x MadMAX DIESEL]

I would not recommend the co pilot to any one. I've had nothing but trouble out of mine. Your list of trans parts makes it sound like you built it yourself, did you do the pump shim mod, you won't get any extra holding power without that?

 

[dwax]

i had a friend at the dealership build it who has built a few before but none that had the power i do. and no i do not have the pump shim mod that i am aware of.. i bought the parts from rob and just gave the big box of parts to my builder

 

[dwax]

I would not recommend the co pilot to any one. I've had nothing but trouble out of mine. Your list of trans parts makes it sound like you built it yourself, did you do the pump shim mod, you won't get any extra holding power without that?

and thanks for that info. i would hate to waste 1000 $!!

 

[x MadMAX DIESEL]

I'd wait for someone esle to chime in though, but I'm 90% sure thats the only way line pressure gets increased

 

[dwax]

i changed the fluid and filter but still acts the same. i know this slippage is killing my E.T.

 

[Evan@InglewoodTrans]

I would not recommend the co pilot to any one. I've had nothing but trouble out of mine. Your list of trans parts makes it sound like you built it yourself, did you do the pump shim mod, you won't get any extra holding power without that?

what problems have you had with your co pilot. i love mine even without it up high when its time to beat on it the truck loves it and all around acts better with it on.

 

[Evan@InglewoodTrans]

not that a co pilot is going to solve his problem either way

 

[MACKIN]

Sounds like your builder either didn't put all the parts in or something is wrong when it was put together. A basic transmission build with the parts described should hold the power your putting through it.

I would assume the line pressure mod is a staple for building the Allison. So most likely you were given the parts. Are they in there,?

 

[dwax]

Sounds like your builder either didn't put all the parts in or something is wrong when it was put together. A basic transmission build with the parts described should hold the power your putting through it.

I would assume the line pressure mod is a staple for building the Allison. So most likely you were given the parts. Are they in there,?

That is the question.. I guess it is time to freshen the tranny up.

 

[LB7Diesel]

Mine did the same thing on a built trans when the clutches were toast. It will only get worse, to a point that any medium throttling in 3rd will cause massive slip. My steels were concave like a saucer dish.

 

[LWATSON]

If you put it in tow haul and select 3rd gear and roll into it does it slip and go into limp mode? I've never heard of an Ally sliping and not going into limp and setting codes. Could it be torque management or somethng. When I had my PPE my truck ran great but it would pull strong in first and second and feel a little dead in third like it was low on rail preasure and shift to fourth and pull hard on up. Same truck with completely the same setup but with different tuning it pulls clean through all the gears. I see you have Robs tuning, I would send him a log so he could look at it and at least eliminate the possibility of something in the tuning. He knows his stuff and could tell you allot just by looking at your log.

 

[dwax]

If you put it in tow haul and select 3rd gear and roll into it does it slip and go into limp mode? I've never heard of an Ally sliping and not going into limp and setting codes. Could it be torque management or somethng. When I had my PPE my truck ran great but it would pull strong in first and second and feel a little dead in third like it was low on rail preasure and shift to fourth and pull hard on up. Same truck with completely the same setup but with different tuning it pulls clean through all the gears. I see you have Robs tuning, I would send him a log so he could look at it and at least eliminate the possibility of something in the tuning. He knows his stuff and could tell you allot just by looking at your log.[/QUOT

Mine is acting exactly like that but has never limped. i will contact him to send a log