400 Turbo Shift Problem

[gearjammer]

Hey guys I'm have a problem with my new car, it will go into rev. neut. and low with no problem, however it will not shift without taking my foot off the gas then hitting the gas pedal hard then and only then will my RPM's drop like it shifted. I have changed the modulator valve tonight with no success.

Anyone have any ideas

Thanks for the help

Phil

[sg7365]

This is a good one Phil.

1. Possible forward-clutch leaks. Oil Pump seal rings worn or damaged. Fwd clutch assy. may have damaged clutch lip seals.

2. Faulty pick-up. Damaged "O" ring or intake pipe damaged.

3. Faulty oil pump and/or pressure regulator. Possible stuck regulator or boost valve.

4. Intermediate clutch malfunction.

5. Another easy one would be is to make sure all vacuum lines are good/ not deteriorated or junk vacuum hose. Make sure all vac lines are together.

6. Check for faulty detent switch operation.

7. Check for loose bolts on the valve body.

8. Is the governor stuck or jammed.

I like to check everything out before tearing everything apart. Use a vac gage to check shift on modulator. Do the easy stuff first, checking everything for tightness.

You may have to drop the pan to check the other stuff-like checking shift detent lever and valve body bolts, oil pick-up tube and "O" rings.
The other stuff requires the trans to be removed and inspected.

I've never had this problem before Phil and I just looked at my 400 book for some ideas.
Hope my two cents helps. I ran a 400 for 20 years and never had one like this.
I tell ya Phil if you overhaul 400's, the rest are a piece of cake. One thing for sure-a full race 400 is a lot easier to build than a street 400----No Balls!!!! Really!!!
Anyone else have any ideas for Phil?
Ron

[sg7365]

One big thing I completely forgot and that was; Turbo 400's are unforgiving for low trans oil.
Make sure its properly warmed up-Do not overfill and keep it at about 7/8 full.

Ron