AutomagicLS1

iTrader: (18)

For some reason I cant keep a 2/4 band in 2 transmissions in my car under 200 miles. I am clueless as to what is going on. First band was a stock band second one was a wide alto carbon 2/4 band which are supposedly indestructable. The stock band lasted longer than the carbon band did by about 50 miles. Nothing else in both trans's are hurt but the 2/4 band. I have looked my trans tune over and havent seen anything out of the ordinary vs what other peoples trans tables look like. I am running 2 large coolers. I have flushed them out and they were free flowing. None of the trans lines are kinked or seem to have any blockage. This most recent carbon band failure was ALL highway miles. No wot 4th gear od which I never do anyway. No racing or anything. Is it possible theres somthing in the wiring harness thats screwed up? I have a new band put in my trans but hell I dont want to put it in till I figure out why im murdering 2/4 bands

Greaseymec

iTrader: (9)

Have you had a shift kit installed recently? Ant adjustments on the 2-4 servo? New servo pin? Servo release spring installed behind the 2-4 servo or broken spring? Not alot of things that will knock a band out that quick. Adjusted too tight or a really screwed up drum. Shift timing could do it but you would also be having a problem with the 3-4 clutches. Does it feel like there is any sort of binding on the 2-3 shift? Have you seen the drum and does it have any blueing?(sign of overheating) Just throwing things out there hopeing one might ring a bell.

Mec

built408

iTrader: (10)

Are you using the old drum with a new band? I always replace the drum when I switch over to a wide band. And I have never really had good luck with the carbon band, I always use the red one. I would check the band clearance and put a no groove pin in it if possible. Other then that, check and double check all the servo orings and sealing rings and the 1-2 accumulator piston for cracks or damaged seal. And air check the servos for any leaks.

FLT

iTrader: (1)

Did you put a pressure gage on it like I mentioned before? You need to recheck all your steps, you missed something obviously to be taking out two bands that quickly. We use both red & carbon bands with no problems FYI, the carbon band works great for us in all our level 5 builds, but you do need to use a new drum when using this band. Take all the above advice and you should find your problem.

Chuck

VortecHOjunkie

iTrader: (5)

I believe there should be about 1/8" of movement on the servo assembly once installed. If there is more than that you may need a new or longer pin. If it is less than that check and make sure you can turn the input shaft by hand. If it is very difficult then the band is too tight and it is trying to engage all the time and will burn it up.

AutomagicLS1

iTrader: (18)

I have used new drums in both transmissions with both bands. I cant test the pressure untill I get it back in the car.

AutomagicLS1

iTrader: (18)

The shift kit is a transgo performance kit. I will have to find out on the servo's all I know is the 2-4 servo is a fairbanks. The guy that put it together is a trans tech at GM and has done alot of local transmissions that are performing flawlessly in some local guys cars here. I'll have to find out about the drum if theres any blueing

Greaseymec

iTrader: (9)

He might be adjusting the 2-4 servo to tight and burning the bands. A quick way to check is to depress the 2-4 servo cover and see if the clearance between the cover and snap ring is no less than about half the width of the snap ring itself. Just a quick way to double check the band adjustment and not the rule.

Mec

AutomagicLS1

iTrader: (18)

How much would the pressure have to be off or too high to burn the band up in 4th gear? Or would that even cause any issues

FLT

iTrader: (1)

High pressure should not burn up a band. Low pressure or a leak in the circuit is what will cause this issue. I personally would get a gauge on this thing to see what is going on. You are wasting your time without doing so. Vince

Greaseymec

iTrader: (9)

Tru Dat!!

Mec

AutomagicLS1

iTrader: (18)

I will definitely do this as soon as it goes back in the car. I wanted to get it out to compare to see if my other trans had the same failure. I just want to make sure I am not overlooking anything that could cause this

FTICONVERTERS

iTrader: (3)

Repetitive band failure can be caused by a worn out valve body in the tcc regvalve bore as 2-4 oil cross at the end of the valve. The acc capsule in the case by the servo can cause this problem as well.

Greg

big wally 55

Like one of the other guys mentioned , the accumulator pistons are bad about breaking . If it is a factory plastic piston don't re use it !If you have replaced the 1-2 acc. piston you have to watch the pin size because there are 2 different sizes !! You didn't say anything about the operation of the trans before it burns the band up ! If you cant do a pressure reading you can narrow it down by thinking about when it was slipping , 2cd or 4th . The band is on in both but it is applied different !
I don't agree with the TCC bore causing the problem but the capsule in the case can cause an almost instant band failure like you are having !!
Make sure there isn't a piece of silicone or other trash keeping the ball from seating in the capsule !