Had dealer increase from 55mph to 65mph, now in limp

[BogeyJoeSr]

I bought my 99 Int 3800 466E 9 window to make a 23ft flatbed. Got it all done, running good but the top speed was 55mph. Drove to the Northern IN dealership where service mngr hooked up his laptop saying it was changed to 65 mph top speed. Upon driving away, it wouldn't shift out of 1st gear. Returned but they couldn't rectify or even get it back to how it was. Any suggestions?

[cadillackid]

What transmission is in it?

[CHEESE_WAGON]

Not sure if this could be a factor, but if it's solenoid controlled, could just be a coincidence that the solenoids began failing about the same time.

[BogeyJoeSr]

Originally Posted by cadillackid

What transmission is in it?

Allison 545

[BogeyJoeSr]

Originally Posted by CHEESE_WAGON

Not sure if this could be a factor, but if it's solenoid controlled, could just be a coincidence that the solenoids began failing about the same time.

Is one of those solenoids towards the top with 2 wires in a sort of magnetic coin? I had it out 300 miles before. Those wires were crossed but i insulated them with black tape and it shifted fine. I'd hate to just start throwing new parts on it. Guess I'm hoping to just get it back to 55mph top speed. At least I'd make money with it.

[cadillackid]

check the trans fluid.. (engine warmed up and running)


does your engine just go to the rev limiter and hold there at 2600 RPM? or does it run up real quick then back down say a couple hundred rpm then go back up.. (possibly dealer fatfingered the keys for the speed limiter and set it at something like 10 or 15 by accident?



check the electric modulator... if the electric modulator stays engaged all the time then it will stay in kickdown mode and never up-shift. there is a transmission relay on the firewall in a group of 3 or 4.. ive seen those relays stick.. you can TEMPORARILY unplug the relay or the modulator itself to test.. the modulator will be about 3/4 way back on the driver side of the transmission.. it is a silver (probably dirty) canister that sticks out of the side of the trans and has a 2 pin connector.. if you unplug itand the transmission shifts then for some reason its circuit is stuck on.. either the relay on the firewall has stuck or the computer isnt releasing the ground for that circuit.


you can also try unplugging the ECM, Gauge, Trans, and Diag fuses from the fuse box with the bus turned oiff and then reinsert them (after making sure they are all good).. this resets the power to the ECM computer.. that might help too..



-Christopher

[Diverdude0075]

Did you get it figured out?