ok this just seems odd to me.
everybody knows when you let off the go pedal the coast clutch in the trans stays locked up until about 40mph or until you hit the brake.

well, mine works just fine in overdrive 2nd and 1st. but when i push the overdrive cancel, when i let off it, the RPM drops way down at any speed.

whats wrong?

 

WHAT?????

I thought for sure id have 20 answers on this by now..

did i word it funny?

 

Yeah, I'm kind of surprised no one has chimed in either. I went ahead and moved this down to the 1999 - 2003 7.3L Powerstroke Diesel forum for you. I'm sure someone in here will jump in.

 

I'm slightly confused. You're saying the OD cancel button does not slow you down on the decline?

 

My OD cancel doe`s the opposite..... engine starts breaking when OD is off (OD-light on)

 

Perfect! It's supposed to do that. If you're towing down a grade, this is a trick to use for going easy on your very expensive brakes and cool your EGTs/engine. All is well. OD light on means you cancelled OD.

 

thats right, when i push that button its almost like shifting to neutral. decline or flat...
the TC is still locked up, but the coast clutch unlocks and then im freewheeling.

 

What does the light do?

"kicks gas"... I like that.

 

my light doesnt work.. i fixed it once before and then it blew out again.

its been a while and i dont remember for sure but i think it was doing it in overdrive and drive going downhill..(thats where i noticed it most anyway, while pulling or just driving un loaded in the mountains) it would be holding then mysteriously unlock, then lock up again, then unlock, so on and so forth.

it was throwing a coast clutch solenoid code, since then ive had the trans out and rebuilt due to other problems, and the solenoid tested fine, and works in OD 2nd and 1st.... i need to do some more testing...

so could this be a solenoid problem even though it works in the other gears?


BTW, thanks for moving the post PS72.

 

I remember reading a number of threads where the OD switch shorts out in the steering column. This may be a symptom of that.

 

The coast clutch is not applying. It could be the coast clutch solenoid, the wiring to the solenoid, or the coast clutch itself.

If the shifter is in 1 or 2 and the truck DOES have engine braking then the coast clutch is working. When the shifter is in 1 or 2 the coast clutch is applied hydraulically, it doesn't matter if the solenoid works or not. If it does NOT have engine braking in 1 or 2 then the coast clutch is not working and the trans has to come out.

 

the coast clutch works in every position except Drive..
the button is working fine, it shifts in and out fine and quick, Ive fixed those wires before... what pushes me is that coast clutch solenoid code that it was throwing.

so can the solenoid work in OD and not not in D????? what i mean is, is the solenoid bad or is it something else like the wiring?

 

Sometimes my skull is number than other times, so I'll repeat back how I understand what you're saying.

• No OD Cancel light, so the only time you know you've activated the OD Cancel is the RPMs will rise in relation to your speed after you've pressed the OD Cancel button.
• OD with the lower RPMs slows you down better than OD Cancel does with the higher RPMs.

Did I get it right?

 

yep thats right, except for one thing,
when i shift out of OD, i get absolutey NO engine braking.
NONE, the engine revs way down to idle @ 800rpm, because the coast clutch unlocks. when i step into it it pulls fine, but i can let off and it falls down to idle.

if i put it back in OD all is fine, the clutch works and holds all the way down to about 40mph, just like its supposed too...

i want to get this fixed so i can play with my exhaust brake. (EBPV)

 

I don't suppose you know somebody with AE nearby....

I have the exhaust braking and man... I'm-a-tellin' you. That hiss isn't as manly as a Jake Brake, but it still sounds like it means business. I guess you could call it a Snake Brake.

I'll break out the book tonight.