3L80 shift problem

[1ghiaman]

I think my transmission is shifting from 2nd to 3rd (D) too early. It's pretty good off the line then go's into 2nd at about 15mph then almost directly into 3rd. At that point I'm at 20mph and it takes about a half mile for the truck to get up to 50mph.

If I shift it manually at 20mph to 2nd and 35mph to 3rd it seems fine. It's still a dog but I suspect that is the way these things are with a non turbo 6.2...

Any suggestions? I have searched around in the tech manuals and searched the forum but have not come up with anything useful.

Thanks in advance.

 

[Bulldogger]

Fluid check?

 

[1ghiaman]

Yes. Fluid is good. BTW, this vehicle is straight off the GP auction so no real maintenance has been done yet.

 

[hmmwv1]

to get the trans to hold the gear longer before shifting adjust the cable.

reomove the dog house and look on the left rear of engine ,under intake manifold, there is a cable that goes to the trans.with the doghouse off hit the throttle pedal and you will see it moving
loosen the front nut in the bracket about a turn and tighten the rear one back up. it will slide the cable in the bracket and apply more trans pressure to shift later
it may take a few times to get it perfect.

 

[1ghiaman]

Thanks for the help. I will check it out. Is that the "modulator link" they talk about in the tech manual?

 

[hmmwv1]

i think so

 

[DatGuyC]

I just thought that was normal haha, my trans shifts so fast and smooth it seems like there is just one gear.

 

[Retiredwarhorses]

That's normal shifting