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Discussion Starter · #1 ·
Here's the back ground
94 RMW stock engine, 4.56 aam gears, trutrack, stock drive shaft
I had a previous clutch problem which I traced to a cracked clutch fork.I was having alot of clutch chatter and hard shifting. this was using the autozone clutch kit.

To solve the above problem I replaced the following

resurfaced flywheel, new clutch fork, new autozone pressure plate and throw out bearing, new mcleod DF clutch disk,

I got everything back together and 1st gear starts from a stop are chatter free, shifting is smooth. However, I am having 2 problems now.

1. When I am in high gears, 5th or 6th under 2000rpm and accelerating the car starts to shudder. This did not happen with the old set up. In fact, with the 4.56's 5th and 6th were actually pretty usable at low speed( under 45) and low rpm(under 2000).

2. I feel a vibration in the clutch pedal while driving (all gears)

Any ideas?
 

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In all the research i'm doing for my t56 conversion, i'm betting you need an alum driveshaft, the stockers won't work (just saying what i've heard) with those 4:56 gears.
 

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Discussion Starter · #3 ·
I don't start feeling driveshaft vibration until about 65 mph
A new driveshaft is on my list of things to get. i wanted to get the clutch sorted first.
I will try doing some 3rd and 4th gears low rpm pulls and see if the shuddering is present. That should rule out the drive shaft.
 

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True, my theory is to get everything correct with the parts, then work out the issues.

Wish I could be of more help.
 

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Possible problem with the Pilot bearing/bushing, or misbalanced pressure plate, it has been a known issue with some autozone pressure plates that they are Chinese sh$% and sometimes more often than not people are having issues with these pressure plates these days.

Now with that being said when you experience the shudder at 2000 RPM are you on the gas when it does this or just enough to maintain 2000 RPM and relative speed? Do you have a way to log your car with datamaster to see what is going on with the motor and to make sure that it isn't causing the issue.
 

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on #1 your "new" clutch may be slipping because it is not yet broken in and seated. in such a high gear and low RPM you "may" be slipping it...

does it have the same shudder if you down shift and accelerate in a lower gear?

#2...sounds like a balance issue. the valeo OEM PP had a paint dab you would line up to the mark on the FW BUT replacement clutches & FW's do not have the paint dab. You could pull it all apart and 180 the PP orientation. Another option would be to have your PP neutral balanced so it's orientation on FW would not matter. FWIW I never had a issue on how I mounted my Valeo/Autozone PP when I had a external (stock) balanced motor.

...and

confirm you are not grounding against anything (x member, exhaust) causing a vibration.

did you put the DS back in the same way it came out (mark U joints)?...if not 180 it's orientation.
 

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Discussion Starter · #7 ·
Mike, its when i am on the gas under load below 2000 rpm.
I have no way to data log. Are you thinking opti spark?
That went through my mind too. Only thing is it wasn't doing it with the old clutch installed. I believe the opti was recently replaced. I will have to check back at the service records the previous owner kept.
But if memory servs there is less than 6000 miles on the opti. Plug wires were also replaced.
 

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Not sure to be honest, but I was thinking for of a detonation thing though, it was tuned right from BH or whoever, I am just curious if there is something up with the tune ad it is causing some retard or pinging under load below 2000 rpm, as this is a heavily loaded scenario being under 2000 rpm and in 5th or 6th gear, shouldn't matter much with the gears that you have, but just curious. It is weird that it came about after the new clutch install. Not sure what to make of it. Is it more of a shudder like a pulsing or a vibration?
 

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Roger brings up a lot of good points, on the T56 install I just did there was no paint dab to go on for it for the pressure plate or the flywheel, so I took a stab and it it came out perfect.

One thing that I am thinking of that comes to mind, how did you deal with the PNP switch as far as the wiring goes for the T56 installation, I had found the same wire that is grounded for the trunk pop is spliced and goes to the PCM for the PNP switch, if this is grounded all the time the DFCO settings, ACCEL and DECEL fueling tables as well as EGR function can be compromised, I just pulled the pin out of the PCM so it thought it was in Drive all the time. I can get you the information if you want to try it or you can go through the massive amount of posts on the last thread that I made for th T56 :)
 

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Discussion Starter · #10 ·
for the PNP I pulled the pin at the PCM
The pressure plate I installed had a paint dab on it but the flywheel did not. However, my old pressure plate had the paint mark and prior to removal I marked the flywheel. So in theory it should be ok unless the new pressure plate is more out of balance than the old.

I just got off the phone with mcleod. I asked them about their pressure plates. He confirmed everyone uses the valeo pressure plate. As far as balancing the guy said they come prebalanced. Their advice was to check the motor and transmission mounts. I am going to replace them since they are cheap and go from there.
They also said i could be over driving the clutch with such a heavy vehicle given that the 6 pucks have less surface area.

Does anyone know what type of clutch Gerry is running on his 95 wagon. On cardomain it says 10.5 mcleod but which disk. Hopfully he will chime in.
 

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Gerry can confirm this but I was under the impression that it is a hybrid, push style. Hell knowing Gerry he probably machined his own pressure plate LOL

Since you aren't having disengagement issues run the 500 mile break in and see what happens as Ball mentioned, he carries a valid point that it could be slipping since it isn't broken in yet.
 

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well the OP says paint dab was matched up as previous clutch...should not be a "balance" issue. possible the DS may be 180 off from previous install but that would typically show as a constant vibration...which this issue doe not seem to be.

Mcleod stateing that possible to 'over drive" the clutch due to 6 puc vs full face in a 'heavy" car. my experience with segmented aka puc disc did not have this problem...but I did not lug in 5th & 6th under 2k rpm....although OP has 4:56 so...maybe that is does not lug at that low of a RPM in those gears. I have 4:10's...also a 383

motor & tranny mounts...could cause this but doubt the sudden change after clutch swap. would be more suspect of something grounding on re-install.

then there is the "new parts are defective" in some way. The PP is cast aluminum...should not be that out of spec if it is. disc....possible it is warped. either came that way or got bent by hanging tranny on it when install. Assume OP has done this before so doubt the later.

just thinking out loud here..
 

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Discussion Starter · #13 ·
question... if the pressure plate is not balance i should feel a vibration no matter what, in nuetral, in gear, or with clutch in?

The thing is I dont feel vibration in the above conditions.

I think 1st step is to look for something binding on the mounts or exhaust
 

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Correct or at least that is the way I think it would work. But you could look at it like a driveshaft as well, if it is out of balance you will only feel it at certain speeds.

Definitely look for scrub points, one to note wound be the tunnel to the top of the trans, on my car it is close where the mid inspection plate bolts are as well as the casting of the rear tail section of the trans, on the car I just got done with I had to "massage" the tunnel to get clearance, as when I first drove the car it sounded like it had a misfire because the trans was hitting the tunnel, but it was only evident when you would torque the drivetrain up like at take off.
 

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Discussion Starter · #15 ·
I just went for a drive. I starting to think the problem is either an out of balance pressure plate or the car is missing.

There is a vibration present from idle throughout the rpm range
I took the engine up to 3000rpm. I can actually feel the vibration in the clutch pedal through the hydraulics.

again vibration is worse under load.

If I were running on 7 cylinders what would that feel like.
I did pull some of the plugs during my transmision install to make rotating the engine a little easier when i checked runout on the flywheel
 

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I just went for a drive. I starting to think the problem is either an out of balance pressure plate or the car is missing.

There is a vibration present from idle throughout the rpm range
I took the engine up to 3000rpm. I can actually feel the vibration in the clutch pedal through the hydraulics.

again vibration is worse under load.

If I were running on 7 cylinders what would that feel like.
I did pull some of the plugs during my transmision install to make rotating the engine a little easier when i checked runout on the flywheel
the car/motor will "vibrate" if you don't have a spark plug wire in or crossed. You would feel it with clutch pedal in or out and more as RPM's increase

since you pulled plugs...possible you crossed something or one plug wire is not on.

a scan tool should show codes 300-308 as a "missfire" with 301= cyl 1, etc.

if you have a grounding aka clearance issue that will certainly transfer vibrations.

on the balance thing...your PP had a paint dab and you put it on same as old one...should be fine. I have never had a balance issue on stock clutch...but it was a "Valeo" vs China knock off
 

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Does anyone know what type of clutch Gerry is running on his 95 wagon. On cardomain it says 10.5 mcleod but which disk. Hopfully he will chime in.
Yeah, my combination isn't usable to most.
10.5 McLeod push type diaphragm , 800 series Kevlar-organic disc, 15 pound steel flywheel.
A little abrupt when hot.

 

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Discussion Starter · #19 ·
well, I found the problem
It was me. I was a bone head and forgot to re-connect the
# 2 spark plug wire.

What suprises me is that the car actually ran pretty well on 7 cylinders.

Thanks for everyones input

John
 
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