• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

2000 GMC 3500 6.5l runs good no power

I goes into PRND but won't go into 321 cable is stops at that point, i too cable off trans t, trans shifts finr

I don't recall if the 2000's had the shift position indicator on the side of the trans or somewhere else. So if the shift position indicator and the physical position of the stuff in the trans is different it may be in a limp mode.

So you can move the trans from P-N-D-3-2-1 ? But not the column?

Someone bolt a wood block under the throttle? Floormat in the way? Bolts to firewall loose on the APP (Throttle pedal and it's attached sensor)?
 
With that being said, I think it should still downshift via the PCM.
Yes, i think so, like every other automatic transmission
I don't recall if the 2000's had the shift position indicator on the side of the trans or somewhere else. So if the shift position indicator and the physical position of the stuff in the trans is different it may be in a limp mode.

So you can move the trans from P-N-D-3-2-1 ? But not the column?

Someone bolt a wood block under the throttle? Floormat in the way? Bolts to firewall loose on the APP (Throttle pedal and it's attached sensor)?
Yes, I can move the shift lever through PRNR. But not 321 i think shift cable is jamed. I pulled cable off transmission and trans shift's through all gears but not cable. Not sure about throttle pedal
 
Hi: Guys, I finally got around to I stalling fuel pressure gauge and boost gauge ,glow shift gauges. It's been too cold here to work outside. Fuel psi at an idle is 10psi at wot is 4.5-5 psi. Boost at idle is 0 at wot is 10psi then drops off as truck shifts up to about 5-7 psi boost. Not sure if 4.5- 5 psi fuel pressure is enough at wot? Dosen't seem to loose any power or change anything, just Dosen't have to much to begin with. I would think it should kick down out of overdrive, like gassers do? Should pull hill easy empty. New injectors, glow plugs,fuel filter, rubber fuel lines under intake, new fuel lift pump.Starts fine in 0 deg temp easy . No smoke at all, clear. All else is stock as far as I know. Thanks Mike
 
sounds like it's running good. mine won't downshift past 55-60 mph but will get there pretty quickly with my foot in it. I know shift points are different between a 2000 and a 95, but I can look at the upshift and downshift tables in the stock 95 tune. it seems that I remember there is a limit on it due to pcm trying to prevent an overrev situation. downshift mostly only happens if hauling a load up hill and loosing speed quickly.
 
I tried yesterday, going up a hill , 45-50 wot it wouldn't down shift out of overdrive , barely made 50 empty. Engine seems to run good though. I know it's not a power house but it should be better than this. My toyota corolla 1.8l with no turbo has more power than this. Is there any performance tunes that might help a little? I have read that changing the timing to -1.50 helps give it more power, but don't want to destroy the engine. I have also read that adding ATF to the fuel helps lube the Injection pump. Thanks for any help. Mike
 
you might want to check codes for the tranny or have a look at data to see if the pcm is commanding a downshift or release of OD. if when your doing this and you manually drop the shifter from OD to third will it downshift and pull harder?
 
Can't drop from OD to 3, shift cable is jamed. It shifts from PRND no problem, I pulled the cable off trans and trans goes threw all gears, PRND321. I bought a new cable just haven't had a chance to install it, it's still cold outside in New york.
 
you might want to check codes for the tranny or have a look at data to see if the pcm is commanding a downshift or release of OD. if when your doing this and you manually drop the shifter from OD to third will it downshift and pull harder?
How does the PCM know to down shift? Fuel pedal, map sensor, speed sensor? How do I check codes for transmission? OB2 connection, does a regular code reader work? Thanks. Mike
 
Back
Top