I know it is... cause everyone tells me not to... and i don't. But what i don't understand is... your never actually "manually" downshifting... your just telling the computer to downshift a gear by changing the position of the shifter. which is the same signal it gets from the computer when you press harder on the gas to get it to downshift, is it not?

i don't get it?

 

its bad when the diesease spreads between auto drivers thinking there car is a manual hmm not sure if it's bad or not, I call upon Rkrause!!!

 

thanks tool...
your cool...
go to school


DISEASE.

 

Now there's no reason to be acting like that. Just give it some time for the tranny builders on here to respond (Pro-Built and 12SCNDZ are two that i'd ask directly).

 

Downshifting puts undo stress on the input sprag over-run lugs, which will cause them to break.

No, "forced downshifts" and "manual downshifts" are 2 different things. Manual downshifts bring the over-run clutches back on...Forced downshifts (pushing the accelerator harder) doesn't bring them on....

As oppossed to popular thought, I've never seen any damage caused by manually UPSHIFTING one of our 60E's

Frank

 

so placing it in 1 or 2, at a stop and allowing the rpms to remain high for say an autocross... is ok... whereas downshifting at speed using the shifter is bad.

correct?

 

downshifting can overspeed the engine.this is dangerous.usually the strategy programmed in the computer for an electronically controlled transmission will not allow downshifts to occur to a lower range until output speed is at a level that will not result in engine overspeeding even when the selector is placed in a lower range.some kits bypass this function and this is dangerous for the internal components of the engine.it usually wont result in sprag failure unless the throttle is lifted and reapplied because of the influence of the low reverse input and overun clutch .the input sprag is at its highest speed in overdrive ,not in any lower range.freewheeling sprag on a downshift can only occur if you lift the throttle after manually selecting a lower gear which disconnects the engine and converter from the turbine shaft and allows the driveshaft to become an input member against the geartrain the .on hydraulic shift 700r4s the transmission will shift from 4th to 3rd and then second even if the selector is placed in drive 2 from overdrive.this is because the 3/2 control or 4/3 control valve and orifices meter the rate at which oil is evacuated from a dumped friction element.however many valve body kits remove these functions making sprag and other parts failures occur.a well designed kit such as ours actually increases clutch exhaust timing to eliminate functional problems and the resultant parts breakage associated with this type of "SMART" calibration.if all is working right engine overspeed and sprag failure wont happen.governor and valve body mismatching can cause these problems with hydraulic shift automatics.ckperformance.com

 

I have been shifting my car for 10 k now but I dont downshift much.I never downshift hard.

 

I dont think it is good on it tho but it hasnt went yet.

 

there is no reason to downshift manually unless your looking to hold an rpm... for like an autocross, in my situation...

anyways back to my second question

also... i know for a fact engine overspeed cannot occur... i can move the shifter all i want... but it won't downshift if doing so would bring the rpms over 3,600

 

K thanks teacher!, just a lil typo!

 

Well my car does the infamous hit the revlimter insted of shift.And i get better times when i shift my car

 

ooook... this means you have something bad wrong with your transmission...

 

mine does that and it was just fully rebuilt, if you figure out how a fully redone trans can peg the limiter with no other changes (except B&M transpak) let me know cause i still havent figured it out and am hoping a computer retune will "help" only because of the later hange to 3.73 gears but it still did that. also im glad i read this post because if i ddint i wouldve killed the 700r4 in my 87 pro/am because ive been manual shifting it up and down a lot lately because it seems to run a lot better that way, guess ill have to cut it on the downshifts though, guess ill just have to start usin the brakes again :-p. some nice info on this page though, makes me wander how some of those manu-matics work wish gm would make us one of those in a 5spd

 

That's not entirely true. Having had both 3.73's and 4.10's in my car, it will NOT downshift automatically out of 4th gear when going any faster than ~70 mph. I HAVE TO pull the shifter back to 3rd manually to get the downshift where I want it to be. Trust me, it makes a BIG difference.