4l60E Shift Killer Q's
 

Alright here we go, got my MS4 cam installed about a week ago (replaced 224/228 cam). Took it out for some WOT tuning tonight and the 2-3 shift tagged the rev limiter :bang: I even noticed the 1-2 shift is a little lazier now too. I'm shifting at 6300 (224/228 cam: 6100) now. I've replace the 3-4 clutch pack with the "Z-Pak," the beast sunshell, 2-4 band, pump slider spring and the rev-kit (clutch release springs). I've only made about 5 passes on this rebuild (2 passes spraying 150 shot) and daily driving it like a grandma. I don't want to pull the trans out and just replace the 3-4 clutch pack and make another 5 passes and have the same thing happen. My question is "What causes the clutch pack failure?" I don't believe the weak clutch pack answer because too many people have repeat failures with the stock or aftermarket clutch packs. I've been wondering if it is a hydraulic problem releasing or applying the clutch packs; basically one clutch pack or band is still applied while applying the next causing it to drag and burn up the pack. Temp was only 141F while testing also. What do you guys think of this theory? Can drilling the apply and release orifice's for each gear help cure this problem? Any other ideas/cures? I can't afford a pro built trans or a TH350/400. Thanks in advance guys!!!

ok a few questions what shift kit did you use and what servo set up do you have ?

No shift kit, Sonnax 2nd and 4th Gear. I have the LS1 edit and on the Line Pressure Table, under Performance shift the tables are all set at 90, is this a direct reflection of line pressure? Where should this be set at?

Raising the line pressure a little as you have done can help , and adding the sonax servo can help to, however there comes a point in which the apply volume and time must be improved as only a shift kit can do. Though you have increased the surface area so your apply holding psi has increased the fluid volume and time to apply has not been increased , This is as if not more important than the additional area , Slip on apply will kill any clutch set or band no matter how upgraded and thats exactly what the stock feed holes and accumulation in the valve body and plate were made to do (soften/smoothe) Shifts .I would suggest a shift kit to address your issue like the transgo ,Thats why when building a trans simply upgrading parts is not enough ,
If we can be of any help let us know

do you sell the shift kit you are talking about from Transgo? If so, send me a PM. If not, can you tell me a good place to get it? What 3-4 clutch pack do you recommend and 2-4 band? I would like to freshen those things up while I'm there. Also, can I get prices on those as well?

Unfortunatly we do not sell parts for transmissions , There are however several vendors on here that do

You could be having multiple issues. Crossleaks in the pump or in the input drum to stator or even in the valve body. We do sell parts if you like to get them from FLT. You could be having a tie up between 2nd and third. This could be a problem as well. Feel free to give Chuck a call to discuss your situation. Vince

Glad I was able to assist you BNK

Vince, do you sell any of the Transgo shift kits? If so, how much do they run? I will give that a shot. My car only has 24k miles on it and didn't start having problems until it got its' new found power...plus the nitrous :) Is there any way that I can check for crossleaks before I drop the tranny? Is that common, to have crossleaks and/or tie up between two gears?

We do sell the HD-2 kit from transgo. I believe all the prices are listed on the parts section of the FLT site. We do see issues with crossleaks in the pumps and also in the input drums with loose shafts. This one of the reasons we prefer to use sleeved input drums and also in house machine all of our pumps. Also if the shaft is loose it could damage the stator shaft where the teflon sealing rings ride. It is always a good idea to flat sand the case and the valve body to insure flatness. A good thing to look at here is the gasket impression of the valve body and the case gaskets. You might want to also check to make sure that that all the seals on your new sonnax 2nd servo are good and not rolled over. It kinda sounds like you might be having a tie up here. This would explain the 3-4 clutch failure in a very short time. No offense, but how many times have you been into this trans? It might be a good idea to have someone look over this unit for you. I'm not bashing you here but I hear similar stories like this alot. I understand if it's not in the budget but something you might want to consider. Vince

I've only been into the trans one time. I had an ASE Certified Trans Tech that works at the dealership with me go through it with me to watch over my shoulder and give some pointers, he knows what he's doing to say the least. I've also rebuilt about 6-7 of these trannies at the shop. The 2-4 servo's have been in the car since it had about 5k miles on it. But I popped them out tonight real quick and the seals look like they are in good shape. I ordered a seal kit from sonnax to replace them on this next "rebuild" just to make sure. Also ordered a Transgo Shift kit, gonna need that regardless. Gonna check some prices and order the 3-4 clutch pack and 2-4 band tomorrow. I've talked to a few different people and they think that the shift kit is probably my problem. Delaying shift quickness and dragging from one gear to the next causing slip and burning up the band and clutches. We'll see what happens!