Transmission Shift problem

[john_V63400]

I have a 01 GA GT S/C V9 vortech blower and so on........
My tranny is stock and has 34,000 miles on it.
I recently started having shifting problems at full throttle shifts.
It shifts fine below 3500 RPMs, but it sits at 4000 RPMs and just doesnt pull after that, and I also loose all accelleration.

I accerlerate full throttle, as soon as it starts to pull to 4000 RPMs it looses all accell power, its like it's slipping and the engine still revs steady at only 4000, but nothing happens, almost like I have thrown it into nuetral and kept the Gas at the same RPM as if it was still in drive.

What do you guys think, anybody have this same problem, Its an auto trans

[3.1POWER]

If it was just trans slippage, your rpms would still increase..... interesting problem you've got here....

[3.1POWER]

One of my friends thinks it may be a timing issue..???

[bszopi]

Neutral saftely switch. If the PCM thinks your car is in N or P, it will not let the engine rev past ~4k.

[tijuana_no]

Neutral saftely switch. If the PCM thinks your car is in N or P, it will not let the engine rev past ~4k.

but,this could be fix with ben's chip.right!!!!!!

[prophiseer]

Neutral saftely switch. If the PCM thinks your car is in N or P, it will not let the engine rev past ~4k.

I was also thinking the manual range valve assembly might be starting to go bad.

Outta curiosity, is it every gear it won't shift, or just certain shifts (i.e. 1-2,3-4)?