2002_Z28_Six_Speed

iTrader: (20)

I am going through an issue where I have to mash my clutch to the floor to get good shifting. I have bench bleed, gravity bleed, and you name it.

To the point where I am thinking the issue is somewhere else.

Does anyone know if these slave cylinder shims might fit? They look like they are designed for a T56 but maybe the slaves are similar enough.



Tick Performance Slave Cylinder Shim (.180") - Tick Performance, Inc.

_zebra

iTrader: (5)

what ended up being the problem/solution here?
just got my nv4500 together yesterday, but the clutch is at the firewall & shift engagements are terrible.
had my wife help bleed the slave again this morning, but not really any better.

stroker87

iTrader: (6)

you have any play in the peddle if not maybe a bad slave?

remember reading someplace if you swap to a NV4500 it takes a different slave? was this a swap or original nv4500?

_zebra

iTrader: (5)

it's a trans swap from a 3500, and the internal slave version actually uses the same slave & throw-out part numbers (verified by multiple parts look-up sources), but i still bought new ones. previous clutch disengaged just fine mid-to-early pedal before. you might be thinking of the early-90s version that did use an external slave setup... i ain't got that one.

i've had a tough time finding the input shaft length of the nv3500 to compare to the 6-5/8" of the nv4500, and my core's already gone, so i can't go out & measure the old trans.

i ain't got any vacuum bleeding tools or anything, and my wife didn't sound too confident with her method/timing of pushing the pedal while i was working the bleed valve... but i just wanted to make sure nobody had to do some weird shimming or anything before i call the shop back (i've got little confidence left in them after the other shenanigans i've dealt with).

dantheman1540

My buddy with the denali asked Z28 about shims and he said he did not shim the denali but he had a whole box of them on his shelf. The Denali shifts okay not shimed so idk if that helps at all.

_zebra

iTrader: (5)

it does - i'm trying to rule out as many things as i can. the blocks/cranks are the same dimensions, it's an OE bellhousing, and i gave the shop a regular Sachs flywheel & LuK clutch/slave. when we were bleeding yesterday, it'd shoot a whole load all over the towel when i opened the screw and doesn't leak anywhere else when pumped with the screw closed.

this is the 5th clutch i've had in this truck, and the only other one that ever felt like this was the 126k mile stock setup when i bought it in '06 (but it at least had normal pressure on the pedal). my '05 d-max w/ the ZF worked at about half pedal, and none of the new '04-05 2500HDs when i worked at the dealer ever engaged that far down.

i ain't smelled anything yet, but the starter seems like it's got a little more drag on it than normal, too... i think i might have my wife hold the pedal down in neutral while i crawl under to see if i can feel the input shaft turning or not. or maybe the battery's just still recovering from where the shop left it on & killed it - requiring a couple jumps on friday.

T-RevMotorsports

I can measure my nv3500 for you if that helps at all. I had a similar issue with a m5r2 swapped ranger. I tried 3 different master cylinders before finally cutting the master rod and adding in a spacer I made to increase its travel. That did the trick perfect and the truck shifted great after that.

dantheman1540

Make sure the shop tightened all of the wires they had to undo it could be the cause of the starter strain.

When I was just bleeding my RCSB clutch I used a hose and water bottle so I could see the bubbles. I was surprised that I would get several pedal pumps with no bubbles and suddenly a few would pop out. Maybe it needs more but I know how irritating it is to bleed and bleed with no results.

2002_Z28_Six_Speed

iTrader: (20)

So the fix for me was to move to the new GM (updated part number) master cylinder. It is still available for purchase last I checked and roughly about 120 shipped. Easy to install as well. Other easy option is to modify the push rod length as stated earlier. Steve's truck does have the new updated part. It helps. Shifts fine. It is still a bit low for me but most people probably won't care. You basically go almost all the way to the floor or skim the floor to shift. In some cases you can get away with 90% to shift. Before the updated master it was 100% to even get a shot at shifting with high effort and occasional grinding. Why did GM not do more for the poor shifting of these trucks???

The tick shims will fit but I never got around to installing them. Had I a shop buddy to help me pull the trans again I would have tried the shims. They are just taking up space right now.

Maybe an aftermarket clutch setup would help as well.

Edit: aww crap its snowing....

_zebra

iTrader: (5)

which master cylinder? i've got the 99-00 one (same as what was used in the 2500 & 3500) & matching slave (again, same in all full-size 5speeds).
the 01-02 style looks roughly similar but moves the slave quick-connect farther up the line.
the 03-06 setup swaps the connectors & roll-pins the entire clutch line to the slave.

either way - changing master styles means pulling the entire transmission again to also change the slave.
requiring full depression to disengage a brand new clutch is unsatisfactory. what's supposed to be the indicator that your clutch is done? or do you just accept 1/3 of its usable life because it can't let go any further? and how's that work for my synchros?

i did just drop the truck back off tonight for the new trans/t-case seal leaking, and when i asked the tech yesterday how thoroughly it got bled, he said likely not enough... judging by the multiple other WTF discoveries i've found, i believe him... we'll see in a couple days.