new trans wont shift

**NEXSTAR7** · 07-05-2010, 12:38 PM

i had a tranny replaced in my 2006 gto. everything was good for 3 months. now i lost 3rd an 4th. dont want to say who made the tranny and who tuned it. i did notice the tune was holding 3rd a little longer than usual. 4th would come on at 55mph. also after the tranny tune i started getting ses lights for crank sensor also trac off. i replaced the crank sensor , but i still get the light to come on once in a while. you think the valve body got something in it to keep it from shifting? or the tune wore out 3rd and 4th?

**Cutlass** · 07-05-2010, 05:34 PM

Sounds like the 3-4 clutch pack is wiped out. Its a somewhat common failure in the 4L60e. I see it all the time. A tune can put a little more stress on that clutch pack but it also isn't the strongest thing to begin with. So it could be either. There are upgraded clutch pack kits out there that fit 9 clutch discs in there instead of the stock 6 disc. Google "3-4 clutch" and you'll come up with lots of info on it.

**NEXSTAR7** · 07-06-2010, 05:24 AM

thanks, will look into it. im very surprized it went so quick. the tranny is rated for 650 hp.

**Cutlass** · 07-06-2010, 06:01 PM

is it possible that the trans was low on fluid?

**NEXSTAR7** · 07-13-2010, 08:47 AM

Originally Posted by Cutlass

is it possible that the trans was low on fluid?

nope. i checked it after. it didnt smell burnt either. it might be a combo of clutch pack and tune. it does hold od from kicking in till 48 to 55 depends on the incline.

**CtheDrTransmission** · 07-18-2010, 09:48 AM

Originally Posted by NEXSTAR7

i had a tranny replaced in my 2006 gto. everything was good for 3 months. now i lost 3rd an 4th. dont want to say who made the tranny and who tuned it. i did notice the tune was holding 3rd a little longer than usual. 4th would come on at 55mph. also after the tranny tune i started getting ses lights for crank sensor also trac off. i replaced the crank sensor , but i still get the light to come on once in a while. you think the valve body got something in it to keep it from shifting? or the tune wore out 3rd and 4th?

First off, smell the fluid. If it smells burned, the second clutch has failed.

Number 2, if it has failed, it has failed because of shift valve in the valve body with faulty design. Most units are still all hydraulically controlled off of an electronic shifting component.

In turn, when rebuilders rebuild a transmission they replace parts. Replacing parts is only a quick fix. When you fix the problem that caused the problem to fail, then you've cured the long term problems hat might exist with the transmission. Fixing the problem that caused the fault is the cure.

There are numerous areas in a transmission capable of improvement that are better efficiency and stronger parts that are available than a factory replacement part.

When rebuilders think outside the box, they'll go the extra mile to replace parts that might fail several months or a year after a rebuild.

There are parts that are designed to fail under heavy duty use, wide open throttle applications, and abuse. The best idea situation is fixing the problems that aren't there, but the problems that will be there after rebuilds or down the road.

I hope I was able to help. If not, let me know.

**Cutlass** · 07-18-2010, 12:38 PM

Originally Posted by CtheDrTransmission

First off, smell the fluid. If it smells burned, the second clutch has failed.

He said he already smelled the fluid and it was ok. And there is no such thing as a second clutch in a 4L60E, so I'm not sure what you're getting at there DrTransmission?

**CtheDrTransmission** · 07-19-2010, 09:53 AM

Originally Posted by Cutlass

He said he already smelled the fluid and it was ok. And there is no such thing as a second clutch in a 4L60E, so I'm not sure what you're getting at there DrTransmission?

The "second clutch", as named in some parts catalogs, is on in 3rd and 4th gear. As far as going to a 9-clutch or 14-clutch clutch pack, those types of set ups are not the greatest choice in a lot of high-performance 700r4's or 4L60E's.

Sorry if I was confusing. I was referring to them as we have since 1982, (when we're doing warranty work on transmissions in the 70's/80's for GM).

**NEXSTAR7** · 07-21-2010, 10:14 AM

Originally Posted by CtheDrTransmission

First off, smell the fluid. If it smells burned, the second clutch has failed.

Number 2, if it has failed, it has failed because of shift valve in the valve body with faulty design. Most units are still all hydraulically controlled off of an electronic shifting component.

In turn, when rebuilders rebuild a transmission they replace parts. Replacing parts is only a quick fix. When you fix the problem that caused the problem to fail, then you've cured the long term problems hat might exist with the transmission. Fixing the problem that caused the fault is the cure.

There are numerous areas in a transmission capable of improvement that are better efficiency and stronger parts that are available than a factory replacement part.

When rebuilders think outside the box, they'll go the extra mile to replace parts that might fail several months or a year after a rebuild.

There are parts that are designed to fail under heavy duty use, wide open throttle applications, and abuse. The best idea situation is fixing the problems that aren't there, but the problems that will be there after rebuilds or down the road.

I hope I was able to help. If not, let me know.

that was a very honest opinion. if i lived in reno, i'd bring my tranny to you . thanks