alright heres the run down. i have a t56 with a 6.0, i have had the tranny rebuilt, but there was no problem found there but i had them beef it up alittle while it was down. i have an ls7 clutch and flywheel, and a f-body slave w/ truck master. the clutch still looks perfect but i cant shift over 4000 rpms. under that though she shifts beautifully. anyone got any ideas im thinkin its the hydrualics but im not sure. thanks in advance, Billy

 

What hydrualic line are you using? SS or the plastic truck line? Did you do the drill mod?

 

yep, . . . . do a search for drill mod on tech, they'll have pics.

 

i have the steel braided truck line that came stock on my truck. i removed the roll pin in the slave and swaped out the f-body end and just connected my truck line to the slave and put the pin back. ill look up the drill mod. thanks for the fast response guys.

 

https://ls1tech.com/forums/showthrea...ll#post4443275

 

Describe what happens when you try to shift over 4K. There are syncos between adjacent gears to spin the gear you are going into(regardless of whether it is an upshift or a downshift) up to or down to the speed of the gear you are leaving. Do you have problems shifting into or out of a certain gear at 4K or do you have trouble shifting at 4K no matter what gear you're trying to shift into?

 

it happens on the up shift in every gear. i thought of the syncros, but when i had the tranny rebuilt they were fine. im workin on droppin everything right now to do the drill mod. has anyone ever had to shim their slave before? just curious if that is something i should worry bout while i have the tranny down.

 

The drill mod won't hurt, but will it solve your problem? I'm not so sure about that. Think about your symptom. You only have the problem on UP SHIFTS over 4K RPM, but not down shifts over 4K RPM or any type of shifting at all below 4K. That narrows it down quite a bit. What do up shift over 4K have in common to the exclusion of all other type of shifting. Not much that I can think of. The clutch "SYSTEM" is worth looking at. Has the master ever been replaced? Have you bled the slave. The drill mod is really only supposed to help a properly working clutch get a little bit better. Not fix a broken one.

 

I had the exact same problem when I went to the track with my T56. I had never really driven it hard on the street, so when I got to the track I was unpleasantly surprised. I would get out of the hole, and then try to shift WOT at 6400ish rpm and I'd have to coast down to around 4000rpm to get into 2nd. I however didn't have the same problem getting into 3rd and 4th.

I had already done the drill mod at this point so I knew it wasn't that. The next day I noticed the hyd fluid level getting lower, so I added to it. Then next day it was a little lower. It turns out the orginal slave I had out of a 99 Camaro went south. I got a new 01-up slave and all was good.

 

alright check this out, i didnt use to have this problem. but one night i thought i felt a "pop" in the clutch pedal. didnt really think anything of it. thought maybe the plastic cup on the clutch pedal had moved or something. but now that i think of it, it wasnt long after that, that i could shift over 4 grand. so you guys think i would replace the slave???? what would make a slave go bad like that? before i had the trans rebuild i put a new truck slave in but that one was it was all plastic and just didnt seem to work either. when i took it out it blew apart on me, so i went back to the f-body slave that i had in there the first time. that slave is an 02 slave, bought it brand new when i did the swap. only bout 6-7 thou. on it.