ok, here's my problem...if i try to accelerate too much while i'm in overdrive, my tranny surges. it only happens when its in overdrive, so i'm pretty sure its tranny related. it doesn't just surge a little...it physically moves the truck. not a lot, but enough for it to knowingly be bad. just curious if anyone might know what this is or have any suggestions. thanks!

 

now when you say surg, do you feel it jolting? could it be a tranny mount? or am i way off?

 

you're way off...it jolts, but has nothing to do with tranny mounts.

 

i don't understand what you're saying.

does the engine rev up to higher rpm's.
is it downshifting, then upshifting ?
is the transmission slipping ?
is the transmission/drive line shaking and shuddering ?
is it one jolt or a series of hammering jolts ?
is the TC unlocking then relocking ?

 

i would check out you TPS(throttle position sensor) its on the throttle body on the drivers side straight across from where your throttle cable is, it has 4 wires i believe. theres 2 torq screws holding it on. its and easy fix if it the problem.

 

Sounds like the Lockup Solenoid.

 

...i freakin knew SOMEONE was going to say TPS or IAC....i knew it. lol.


regardless, whats the lockup solenoid? i seem to remember it being almost like a separate unit, kinda like the governor pressure sensor and solenoid.

 

well the surge is a common problem while driving down the road. and the tps feeds the throttle position reading to the pcm which controls tc lock-up, and a fluctuating reading from the tps would make the pcm think you were moving in and out of the throttle, which in turn locks and unlock the tc.

and the iac has nothign to do with this, as it prevents back fireing when you let off the throttle, and it keeps the idle steady in different temperatures, and air pressures

and after re-reading your post, im going to say its the tps, because you said it happens when your accelerating, and the surge is caused by a fluctuating reading from the tps. which is tranny related.

 

very well, i stand corrected. haha. its a recently new tps, but i shall go out and buy a new one just to see, i can always return it if its not the problem. just for clarification, how does the t/c lock up work? thanks 004x41500.

 

no problem, these computers have gone way beyond most people, unless you work everyday with them, and experience these problems you would think that it was something different. as i was having random shut downs off my truck, many said it was the crank sensor, cam sensor, or fuel pump(which in fact did go out as well but it wasnt the problem) and it ended up being a faulty pcm, as i managed to pick one up form the local junk yard for 75 bucks, and swapped it out when it shut down, she started right up, and i havent had a problem since(knock on wood)

as for the t/c lock up my understanding of it, is 1,2,3, o/d, tc lockup some say its 1 2 3 lockup o/d,but i would say it varries dependant on certain conditions and is determined by the pcm. and it further decreases your engines rpm as it locks up the t/c which in turn entirely eliminates any slippage there and it makes it a direct drive into the trans.(im no expert but this is what ive learned here on the site, thank guys)

ive read on here that there were a few guys on here with new tps's and they had problems, it seems these magnum motors are very picky about parts. your best best would be to get the tps from the dealer, if youre able to afford one(no pun intended.)

i would try to swap a new one out, or a known good one(e.x from a friends truck or soemthing) and see if your surge goes away, before saying its in the tranny, as the tps is a much much cheaper fix even if you buy it from the dealer.