Sluggish Transmission

[stal023]

Posting to see what everyone's opinion is on this: I am wanting to buy an AWD to convert it to a camper. Here is something on a 2001 GMC Safari AWD with 125K that has a rebuilt engine. Shifting to D(rive) the van doesn't have the get up and go it should, feels sluggish. If you manually run it through, it is fine. One thought was it could need new transmission fluid (Although it appeared clean) or it could have a plugged filter, or the shift solenoids are shot. Opinions?

[okie1]

Could be a ton of reasons, take it to a reputable shop and have it tested, it will save you a bunch of $$

[stal023]

I am, but I thought it wouldn't hurt to hear everyone's opinion on here

[okie1]

There are a few shops around here that do not even charge for diagnostics, you may find one in your area. Without driving your vehicle it would be only a guess. good luck, let us know.

[Mmusicman]

Engines are usually described as "sluggish"... but not typically transmissions.
Often times symptoms between the two can get confused as well.

However, you describe that manually shifting does help with the problem, which certainly seems to describe an issue with the transmission. Manually holding a transmission in gear can also affect engine vacuum... so then we're back to the engine.

Is the transmission slipping in gear, or is it slow and "sluggish" with the shifts?
How does it do with heavy throttle shifting?

When a transmission is "manually" shifted into 1st or 2nd gear, it should be noted the hydraulic pressure is boosted to full pressure. This can aid with towing or pulling a heavy load while in low gears, and will also have an effect on the shifts as well.

If internal pressures are abnormally low in drive and overdrive, this could lead to slippage and eventual catastrophic failure as well. I would certainly have it tested.

Don't make expensive assumptions.

Let us know what you find.