firm shifts
 

I have adjusted my modulator on my th400 to raise the shift points up to about 3900-4000 at wot, get a nice chirp on shifts now. But at regular driving it shifts very firm. My tranny has been rebuit with a stage 2 b&m shift kit. Some people say that firm shifts are good for tranny others say no just wondering your opinions?

Re: firm shifts
 

my bro just a put a tranny in his 88 gmc that was rebuilt for towing and it has firm shift especially out of first into second also my parents 00' silverado has tow haul which raises the rpm's and makes quicker firmer shift for towing

Re: firm shifts
 

as long as it's not slamming at low speeds you're fine.

Re: firm shifts
 

define slamming

Re: firm shifts
 

my tranny guy told me the quicker it shifts the less wear, and slippage on the bands.

Re: firm shifts
 

got one in mine... love it. mod. not as high as yours but high. less wear on the bands... harder on the gears...

--den

Re: firm shifts
 

yep, the firm shifts are eliminating as much slip as possible betteween gears, but that directly puts more impact on the diff and ujoints. its a give n take situation.



slamming would be neck popping tire burns at every gear at any speed.

Re: firm shifts
 

sound like your line pressure is too high at part throttle. when i had my 700 built it was like this at first but the tranny shop fixed it. he told me it might need to be adjusted but to drive it first and see. it would chirp tires going slow through town. way too harsh for every day use. a few months later (even though i got the prob fixed after a week) i had to replace a u joint