Hello all, I have a th400 with a factory high stall, dual feed mod, and a auto/manual Hughes valve body. My issue is that 1st gear works up until 35-4k rpm off the hit then the motor is spinning still under load but it pretty much stops pulling. Throw it in second tires chirp and all is right. But missing half of 1st gear is really killing me off the hit. Any advice on what's causing this would be great... Tranny leaks some was rebuilt a couple years ago, chasing down the leak. 1st gear has never been right.

 

Is the valve-body a modified-stock/ OEM type valve-body?
Forward shift pattern and engine-braking?
Does the unit use a vacuum modulator?

Is there is difference in transmission operation, between the manual-low gear-selector position and the D2 or D3 positions?
Was anything recently changed in the transmission?

Does reverse operate properly?

You should really purchase a line pressure gauge and see what the pressure readings are for all the gear ranges.
Honestly, this is something everyone should be doing before starting a thread on the Auto. Trans. forum.

 

It is a modified stock type with engine braking and modulator, it has manual 1 2 and won't shift 'til you make it and a regular drive 3rd.. 2nd and 3rd make it pull like a semi just first craps it's pants after 4k rpm.. And reverse works great shifts are firm.. Only time I notice is when I dig race placing it in manual 1st which is often. Vac modukater shifts before it is noticeable when spun that high in drive

My shifter linkage pulls it as far as it'll go back on the trans.

This has been an ongoing problem for awhile.

Sorry I'm not good with trans or I would've known to have one hooked up
thanks!

 

No bleed hole in the direct drum.