Transmission 3rd and 4th gear fall out

[Cobra]

Driving today on highway and drive gear just fell out. Dropped to third and the same. Had to shift down to 2nd gear to get to my destination.
No codes on programmer. (Hyoertech programmer) i set back to factory setting and tried again. Drive starts off and then just falls out. At lower speed appears to drop in hard but then right back out.
Do you guys think tranny is done or is there something i should look at before taking to transmission shop?

 

[swathdiver]

If there are no transmission codes then I reckon it's time for an overhaul with performance upgrades.

 

[Cobra]

What upgrades should i look into.
Shift kit, corvette servo? Any recommendations.
Currently not in a position to have Tahoe down to long.

 

[6speedblazer]

3/4 clutch pack is dead. time for a rebuild

 

[00'BlueSteel]

Best bet is to tell a transmission guy what you do with it and how you would like it to behave after the rebuild. I just had mine done and here is a short list of the big stuff.

Corvette torque converter with a 2500 stall
Beast Sun Shell
HD front and rear planetary gear sets
Transgo HD2 shift kit
Zpak Clutches
HD wide bands

You can also add billet servos, billet input and output shafts, stronger flexplate, have them check and replace rear main seal if need be while they are in there. Not sure if yours if 4x4, you can also get a transfer case case saver put in at the same time as well.

Best of luck, it can get pricey quick.

If you have time ordering a Performabuilt transmission would also be a great option.

 

[Chubbs]

I have read along several different sources where the 3/4 clutch pack fails due to 3rd accumulator capsule leaking. I'm sure most folks who rebuild/refurbish are aware, but if the capsule isn't inspected & tested, the failure will continue to occur until it is addressed.

I don't like f***ing with s*** so naturally, I would be asking questions and voicing my concerns in regard to this if I were in your position.

 

[Cobra]

Best bet is to tell a transmission guy what you do with it and how you would like it to behave after the rebuild. I just had mine done and here is a short list of the big stuff.

Corvette torque converter with a 2500 stall
Beast Sun Shell
HD front and rear planetary gear sets
Transgo HD2 shift kit
Zpak Clutches
HD wide bands

You can also add billet servos, billet input and output shafts, stronger flexplate, have them check and replace rear main seal if need be while they are in there. Not sure if yours if 4x4, you can also get a transfer case case saver put in at the same time as well.

Best of luck, it can get pricey quick.

How do you feel about that 2500 stall? Daily driver?

 

[00'BlueSteel]

It is my daily driver I haven’t driven it that much just got it back on the roads this past weekend. The stall is perfect for my big tires and lift kit.

 

[Rocket Man]

Just curious, but what exactly did you change with your Hypertech programmer as far as the transmission goes?

 

[kurtibm]

I have built a few of these. Sun shell is the likely culprit of your symptom - The Beast is what you will want - and obviously a new converter. Also Corvette servo and a new EPC. If a good master kit is used, (Raybestos clutches) they should more than suffice unless you are boosted. If the truck shifts how you like, keep the standard valve body config. - if you like firmer shifting under acceleration, then go with a shift kit. If you got 150k miles+ out of the current one - the remaining parts are not 'bad'... just 'proven'.
Built as above, a good independent shop should likely get you going for under $2k. parts are about $335 @ cost; yes, including rebuilt converter. R&R about 5.5 book hours and 8 to disassemble, inspect, clean and rebuild. Rear main is a must-do. Consider checking U-joints as well.

 

[Cobra]

Just curious, but what exactly did you change with your Hypertech programmer as far as the transmission goes?

Shift points and shift firmness are the only changes i can do

 

[Rocket Man]

Shift points and shift firmness are the only changes i can do

Unfortunately that might have done it for an old transmission. If the line pressure was increased it could have at least contributed.

 

[Cobra]

Unfortunately that might have done it for an old transmission. If the line pressure was increased it could have at least contributed.

Maybe but I've been using that hypertech programmer for 7+ years..
Maybe over the time caused it. I did make 196,496 miles on this one.

 

[Cobra]

I have built a few of these. Sun shell is the likely culprit of your symptom - The Beast is what you will want - and obviously a new converter. Also Corvette servo and a new EPC. If a good master kit is used, (Raybestos clutches) they should more than suffice unless you are boosted. If the truck shifts how you like, keep the standard valve body config. - if you like firmer shifting under acceleration, then go with a shift kit. If you got 150k miles+ out of the current one - the remaining parts are not 'bad'... just 'proven'.
Built as above, a good independent shop should likely get you going for under $2k. parts are about $335 @ cost; yes, including rebuilt converter. R&R about 5.5 book hours and 8 to disassemble, inspect, clean and rebuild. Rear main is a must-do. Consider checking U-joints as well.

Just came back from a place and they wanted 2k for plain rebuild no upgraded parts. I asked about getting upgraded parts and he said he doesn't recommend oon a standard vehicle..i just laughed because he is telling me this without knowing anything about my Tahoe. Then starts showing me a book of pictures of transmission internal parts. I don't know i just think he was trying to make it complicated.

 

[kurtibm]

If a trans shop does not know a 4L60 inside and out... RUN!

 

[Jamesd546]

Just had mine rebuilt at the beginning of this year. Sun shell failure mixed with a pump failure made $2500 magically disappear from my account.

I don't mind the higher cost though...the shop had excellent reviews and a 3yr/50k warranty which is almost unheard of.

If you're in the Sacramento, Ca area, look up Capitol Transmissions in Citrus Heights.

 

[Cobra]

Just had mine rebuilt at the beginning of this year. Sun shell failure mixed with a pump failure made $2500 magically disappear from my account.

I don't mind the higher cost though...the shop had excellent reviews and a 3yr/50k warranty which is almost unheard of.

If you're in the Sacramento, Ca area, look up Capitol Transmissions in Citrus Heights.

The dealership quoted me at around 3,200 to $3,500 with a 3yr 100,000 Mile warranty.
I haven't decided yet. Been thinking of maybe just ordering transmission like one from www.rpmtransmissions.com
Would like to make some upgrades in the future to the Tahoe in general.

 

[Justin]

I ran an RPM level 6 in my Silverado SS and it shifted quite well. We've dealt with thousands of modified transmissions over the years and we've only encountered a few lemons from the big name trans builders out there.

You will absolutely not want to use the hypertech with any upgraded valve body components or aftermarket torque converter. Increased shift pressures can quickly lead to a snapped output shaft.

 

[Cobra]

I ran an RPM level 6 in my Silverado SS and it shifted quite well. We've dealt with thousands of modified transmissions over the years and we've only encountered a few lemons from the big name trans builders out there.

You will absolutely not want to use the hypertech with any upgraded valve body components or aftermarket torque converter. Increased shift pressures can quickly lead to a snapped output shaft.

A custom tune is what i want. I know the hypertech does not match the level of a true custom tune. I just kept running it because of the millage. I was afraid to break something. Now that the time had come to upgrade, i want to start to get what i really want out of this Tahoe.

 

[Mechanic421]

You my want to check out sonnax web site. They have a 4l60 heavy duty truck build. I just built my self but have not installed yet ,hope it works. But any way sonnax said beast is not the way to go. Check out their smart shell. Not trying to step on any toes! So hope no one is offended that I am dissing the beast!