That seems kinda high....... Even with 4.88's.

 

yeah i thought so to turns out my speedo is off more than i thought sitting 2400rpms @72 mph...amen for tom tom

 

If you think that's high then you should see my Camaro, it pulls 3800 at 60mph (4400 before overdrive kicks in). Then again, I think the tach is busted in it.

 

no over drive in my truck due to the wrong year trans in my truck. 285/75/16 tires stock 3.55 gears at 70 my tach is barely at 2800. you got something wrong there bud.

 

So, with everyone's input, I have moved form suspecting something was not right to knowing something is definitely wrong.....

I have been mentally tearing the transmission apart and putting it back together, checking my notes (yes, I took notes while rebuilding….don’t ask..) and reading the FSM again. I think I have it down to one ore two possibilities, or a combination. I will attempt to verify OD pressure with a gauge set, hopefully this weekend. I know what the scanner reads, but a gauge will either verify or contradict this. This may isolate the problem to the valve body.

The other possibility may be the OD piston spacer thickness. I was on the low side of the tolerance, and the piston may not be applying sufficient pressure on the OD unit. Just cannot decide if I can pull OD off without pulling tranny. May try it, worst thing would be to have to drop rest of tranny to reinstall I suppose.

Still driving truck to office (a whole 10 block commute) and around town, but with this poor mileage, not taking any road trips soon!

Anyone have any thoughts that agrees or disagree with my theory?

 

I could be totally wrong and probably am, but I don't think pressure has anything to do with OD. Isn't that one part of the tranny controlled electronically only?

 

Im pretty sure your right because on my 01 off-road I had to have the solenoid or whatever replaced for the OD or some sort. Hell maybe we are both wrong and Im just mistaken. Wouldnt surprise me.

GDSTOCK i went out earlier and at 70mph with OD on im at about 2350rpms. Thats with 4.10's and 33's.. Something sure aint right in there

 

Funny thing is I also took notes on my tolerances when I did my rebuild...I'm **** like that. MonteC told me that you should always run it as tight as you can get away with (OD piston spacers and shims) because you have to compensate for the wear and tear that you'll put it threw over the years. That way, if you run it loose, months or years from now, you won't run into problems.

 

That doesn't sound too far off bro.

 

There is an OD solenoid that sends pressure through the intermediate shaft (i think) to energize rthe OD piston, mounted behind main case and covered by OD case. The piston is about 8" or so diameter.