Falling on it's face

[Rookie]

This question could maybe go in a couple other places but since it really happens when I'm towing I'll start it here. I've began to really notice or rather it's starting to get to me, that when the TC locks up the truck just falls on it's face. I mean it really drops in power. I had the horse trailer on with one horse, coming on the freeway and when I got on it and the TC locked it was like shifting from second to sixth. Maybe I'm doing something wrong but I can't figure out what. Would a chip make a difference? I'm pretty happy with the power without a chip but... I don't think you can change when the TC locks up can you? Anyway thought I'd through this out and see if anyone else experienced it or had any suggestions...Thanks
Ron

 

[BJS]

well I have a similar truck and have the same problem with mine, when I bought mine I didn't have this problem but only after towing some heavy loads did I begin to see this appear. I have a chip and in or out it does the same thing. What I'm thinking causes it is the torque converter is beginning to fail or there is not enough pressure to transfer enough power b/c when the torque converter locks under heavy accel I'll drop 1300-1400rpm.

 

[Rookie]

Ok, thanks for the reply. At least I'm not alone...I'm going to go back to the guy that rebuilt my tranny and see what he says. Maybe he'll have an idea or two also.
Thanks

 

[CHPMustang]

Typically when we're getting onto the freeway via the onramp we keep the tranny OD locked out till we hit 55-60 MPH to prevent the RPM dog as you seem to be describing,has that worked to your advantage Rook or is it beyond this?

Bill

 

[95_stroker]

I think with custom burned chips you can control TC lock up Rookie.

 

[Rookie]

Bill, how do you keep the TC from locking up? Where it really falls down is on a clover leaf type on-ramp. Theres one here you can only take (at least with the horses loaded) at about 25/30 mph. It's up hill and short. Normally I'm coming out with the O/D off and as soon as I get straight I'm on the pipe and then it locks up and there goes the power. I'm sure it's always been there but now it's just getting agravating...and I'm going to look into a chip and see how much it can control the tranny but if theres a way to change how I drive it I'm open for suggestions.

Ron

 

[CHPMustang]

Bill, how do you keep the TC from locking up? Where it really falls down is on a clover leaf type on-ramp. Theres one here you can only take (at least with the horses loaded) at about 25/30 mph. It's up hill and short. Normally I'm coming out with the O/D off and as soon as I get straight I'm on the pipe and then it locks up and there goes the power. I'm sure it's always been there but now it's just getting agravating...and I'm going to look into a chip and see how much it can control the tranny but if theres a way to change how I drive it I'm open for suggestions.

Ron

I believe TBAR has one of those TC lockout switches on his truck,maybe he'll chime in too

The #2 gear should hold you well at 25-30 MPH just have to manually shift into it but I'm in no way a 4R100 expert around here as I'm only stating how I've towed with our X

 

[BJS]

I don't think that keeping the tc unlocked is going to help it's that there is so much difference between engine speed and vehicle speed. Which leads me to the torque converter or slipping clutches in the tranny though my first guess would be the tc since when it locks drivetrain rpm matches engine rpm.

I'm planning on replacing my tc later this year which depending on funds will either be a good aftermarket one or possibly just going w/ the bolt in option of the 4r100 tc which is a bit stronger than the factory one from the e40d.

 

[Car_nut57]

It sounds like the TC is going away to me to have that much slipping going on that the engine rpm is too slow when the TC locks up. Here is a simple thing to try which may or may not make any diffierence, but it will make your wife wonder what you are doing when you tell her you are training the truck. Lift both battery terminals, flip the switches lights etc. to make sure the PCM is drained. When you reconnect the batteries drive the truck the way you want it to shift, ie: lifting the pedal when you want it to shift etc. Sometimes the computer just needs to learn how you want it to shift again as they do adapt somewhat to the way they are driven. I doubt this will solve the problem, but its worth a try.

 

[Rookie]

The rebuild on the tranny is just over a year old. New and upgraded everything. I hope the TC isn't taking a dump...guess I'll head back to the tranny shop and see what they say.
Thanks for the info
Ron