Tranny gone? Need help please!

[derek_silverado]

Alright, I got back from my trip today and my dad told me my transmission wasn't shifting into 3rd gear. I had just gotten my tune in the day before I left, with a lil firmer shifts and raised shiftpoints (to 5900). He drove it a little bit and got on it just a lil from what he said, nothing too crazy.

My dad said initially it was giving him problems on the way into town with the tach kinda jumping and it not feeling right and then on the way home it it went to second and just flew out as it would go into third, but could be brought back down to a lower speed and second would work. Now once it tries to shift into third and flies out of gear it will not even engage second. I have to stop it and let it go to first and shift to second but I have to keep below about 30.

FWIW I tried getting to third in Tow/Haul mode, which the tuner did not touch, but it does the same thing -- flies out at what would be the shift to third.

What are my options here guys? What will a rebuild cost me if I want it to last while handling power and maybe seeing the drag strip once every month or two? Could it not actually need a rebuild, but maybe something minor?

This is a 99 4L60e with 80K, a vette servo and slight tranny tuning.

Thanks!

[Dark Knight]

Sounds like one of more of you shift solenoids is on its way out. At least that was part of my problem that lead to my second rebuild.

[Hit Man X]

If you only have 1st and 2nd but no 3rd that means no 4th either... so once can assume your 3-4 pack is burned up. BUT You could try a few things before taking it apart... a simple fluid change to see if that helps. Your valve body could just be full of metal filings, the filter clogged, or the o-ring plugging up the pump.

I doubt it's a shift solenoid as when they are both off it's for 3rd gear as I recall.

Like this...
1st A - On, B - Off
2nd A - Off, B - On
3rd A - Off, B - Off
4th A - On, B - On

So hrm. Maybe your EPC solenoid is bad? That controls line pressure, it's worth a test before you rip it out. You could stick a pressure gauge on the case to monitor base pressure as well as line rise.

How else do ya drive it? Any nitrous or anything? Neutral drops?

Do you plan to stay N/A or ever want to get some nitrous? Then I can recommend some parts...

[derek_silverado]

A guy on another forum thought it was a 3-4 clutch pack too.

I put my old tune back in as Brian Herter recommended and its still the same way. It feels fine until it tries to get to third.

As far as use of the vehicle:
It is pretty much a street truck. I was planning on going to then track for the first time ever this weekend.

There is a chance I will leave it alone after I get the tranny rebuilt, but my plans are the following:
75-100 wet shot
TCI Streetfighter
Limited Slip
Nittos

That would be the end of it. How serious of a rebuild will I need for it that? What would be the cost difference if I hjsut have it rebuilt and don't ever touch it again?

The wet shot really is the last thing I plan to do, though... and there is only a 50% chance I will get it.

Thanks a lot for the help!
-Derek

[Hit Man X]

It may or may not be the 3-4 pack, you aren't making an assload of power enough to smoke them IMO. And your milage is 80K. It could be a boost valve or the pump itself is going bad also.

Well if you plan some moderate squeeze, I'd probably go for most of the internal upgrades.

29 Element Foreward Input Sprag - far better in HO applications
13 Vane Pump Conversion Kit - extra fluid flow at higher RPMs
Heavy Duty Reaction Carrier Shaft - eliminates need for thrust washers, works in conjunction with the Sun Gear Shell
Heavy Duty Reaction Sun Gear Shell - limits cracking and splitting on bearing area
Heavy Duty Input Shaft and Drum - limits stress cracks on drum, limits broken shaft
Heavy Duty Output Shaft - limits broken shafts on high RPM kickdowns
TransGo shift kit - .500 boost valve, HO Pump Spring, 1-2 accum spring, fixes problems like...3-4 burnup, 2-3 overlap, delay bangs, poor 3-2 kickdown, etc. PSK or HD2 kits.
Superior Intermediate Super Servo - greater band holding power, much better 2-3 shifts, excellent 1-2 shifts, 35% more apply than 'Vette servo
Superior Overdrive Super Servo - greater holding power in 4th, much better 3-4 shifts, 50% more apply than OE part, comes with billet cover too

Sonnax Pinless Aluminum Forward Accumulator - Stock can be plastic, this is pinless
Sonnax Pinless Aluminum 1-2, 3-4 Acuumulator - Stock is usually plastic, cracks, loses pressure.
Sonnax Servo Release Check Valve - Limits 3-2 downshift tieup/burning

2-4 Band - Black Kevlar Lined 2-4 Band OR Kevlar (Std) 2-4 Band OR Alto 2-4 Band (Alto and Std Kevlar requires wider input drum) - greater holding capacity, less likely to break off band anchor than OE, anchor on the Altos are 60% greater. Oversized Kevlar and Alto are 3/8 wider that stock band. Most late hardened input drums from TDE are ready for the wider band. The standard band is still wider than pretty much all other transmissions so it's not a necessity. I'd run a Red Alto one...Kevlar likes to burn and you're not going to give up a lot on the shifts with the Alto band.

3-4 Clutch Pack - This is highly debated. 6 Blue Plates, 8 BW Tans, 13 in the Z Pac, 9 Alto, etc. Whatever you choose, I'd try to stick with the OE thickness steels to resist heat. That usually limits you to 8 clutches, so pick your poison there.

Low/Reverse and Forward - You don't need anything exotic here as these are only applied from very slow speeds or in a stopped position. Again, pick what you like.

[derek_silverado]

Wow!

Thanks for the info.

What do you think that would cost me.... for some1 else to put it?

Thanks again!

[Hit Man X]

Factor about $600-800 for labor (a day or so) then add up the price of parts. You'd be all said and done for probably like $1400-1700...

Not cheap, but it'll be stout and hold up very well to most anything you can throw at it within reason. That's what it costs. You may be able to skip the hardened input drum and shaft assy but with nitrous maybe I'd try to get it...it's about $300 more. Also the better output shaft will allow you to kickdown from higher RPMs to max out the LS6 cam you're running too.

Again, I'd run a few tests before just to be certain the 3-4 pack is burned up. I'm leaning just a bit more toward to the 3-4 pack now but your milage is pretty low and you're probably making about 300rwhp with that LS6 cam. Stock F-bods make those with the same 4L60E but weigh a bit less. So it's a toss up.

It's either something stupid or toasted.

Do you have access to tools and what not to run diag tests on it?

Have ya posted up anywhere other than on FSC to get other input?

[derek_silverado]

Thanks for all this input man!

I have posted on LS1tech too.

Alright... say I didn't want to go spray and the most I wanted to get to was say 350RWHP..... would that change what all I needed?

I'm intimidated by this b/c I'm young and I only know so much about this stuff and I don't want to go to a shop and get screwed. So, basically I could discuss my goals and problem with the shop, tell them the parts I will buy (what you suggested) and ask what else they think I will need and how much they will charge me?

Thanks!

[Hit Man X]

Well note that torque is the enemy here, not horsepower. Nitrous usually makes a lot more torque than horsepower (like boost does) so that's why I'd go with the harder input and output shafts if you plan to use nitrous.

If you're 100% sure you're not going with nitrous and going to stay N/A... then you don't need the hardened input shaft, hardened input drum, but I'd still consider that output shaft for high speed kick downs to take advantage of that cam.

The other stuff is pretty much necessary lol

I'm happy to help so ya don't get bend with sand in the KY

[derek_silverado]

Thanks again!

A friend of mine had his 93 truck trans (is a 93 a 4l60e or a 700r4?) for like ~650 and it was suppose to be a good, strong build. He only drove it for about 6 weeks before he sold it but he said it shifted very well. He had to pull and install the tranny himself.

I could do that, beef it up some, and get a stall and be like 1300 for a good rebuild and a nice stall.

I'll see how it goes I guess.