08 ACR clutch issue

[toomanymodz]

Ok, I took my new ACR out for it's maiden voyage and after about 15 miles I noticed the clutch engagement getting ever more closely to the floor. I turned around and started heading home and it got worse. Soon the engagement was completely to the floor and I could barely shift gears. Finally the pedal travel was almost all 'slop' with no ability to disengage the clutch. By a miracle, I was able to time the redlights so that I wouldn't have to stop, and I rolled through 3 stop signs in order to make it home. I had to push the snake into the garage, for there was no way to disengage the clutch.

I called John at Roanoke and he seemed to think it's air in the hydraulic clutch slave that was probably there from the factory and worked itself into the lines. He recommended letting the car sit for a few hours and try it again to see if the pedal comes back. I went out and grabbed some dinner and when I came back, sure enough the pedal was firm again, with the normal inch or so of 'slop' at the top. I fired it up and was able to engage/disengage first gear.

The crazy thing about this is I had this exact same issue occur when I bought my 06. Has anybody else had this problem? Or is it by sheer stroke of bad coincidence that I've had two similar failures in a row. I'm nervous about getting out in traffic again. I was on a four lane divided where people zip along at 60+ mph, so this has about shot my nerves for this evening.

 

[bluestreak]

Assuming you plan to drive the ACR like it's meant to be (on track) I would get it serviced anyways as that is not something you'd want to happen at the track. Not only dangerous, but could blow a track weekend costing all the money for fees and such to get in, travel, etc.

 

[toomanymodz]

John's going to let me talk to one of his best techs tomorrow, so maybe we can get some info on what caused this. Who knows, maybe the air has 'burped' out of the lines and it's good to go... but maybe not. I'll find out tomorrow and share the information.

 

[Mopar488]

Mine acted a little weak too when I first got it. I posted about it also. I now have 575 miles and it seems to be staying a about an inch of play. Hopefully it will work itself out in time like mine did.

 

[Tom Sessions]

At VOI A customer came in with his new acr drove it from Woodhouse to VOI .600 miles and had the same problem.We bled the clutch changed the fluid to Motul 600 took it for a test drive . He said that this was the best the clutch had felt.As far as I know he didnt have anymore issues after that.Let me know and I can talk you through the procedure if you dont want to go to your dealer.

Tom

 

[EZ 2B Green]

I had the exact same problem on the first drive with my 08. The solution is to bleed the clutch. This is very easy on the 08 since there is a bleeder valve built into the transmission case. I did mine myself. It took two separate bleed sessions for mine to get the air out and now it is perfect. I just put 2000 miles on the car driving to VOIX and back and the clutch engagement was consistent the entire trip. Just pick up some DOT4 brake fluid and follow the instructions in the service manual if you don't want to drag it to the dealer. I think the fitting is 13mm on the bleeder if I recall. Good luck!

 

[EZ 2B Green]

I forgot to mention that the symptom is temperture related just as you experienced. Once the car cools down the clutch will seem fine. Don't be fooled, it wont fix itself.
Bleed it cold.

 

[HSSSTOY]

Clutch related..08 ACR, after driving for a while, when in neutral (clutch is disengaged) there is a rattle, once clutch is engaged rattle is gone...has anyone experienced that, my tech. says it's normal!!

 

[Bobpantax]

It sounds like someone did not do something he or she was supposed to do on the assembly line. I wonder how many '08s have the problem. Perhaps there should be a partial recall for this issue. I can envision someone driving in a spirited manner on a road course; attempting to downshift; and getting no clutch. It would be a troubling moment.

 

[Bobpantax]

Clutch related..08 ACR, after driving for a while, when in neutral (clutch is disengaged) there is a rattle, once clutch is engaged rattle is gone...has anyone experienced that, my tech. says it's normal!!

Neutral gear rattle is normal in all generations of Vipers. It is a bit worse in the '08 because the tranny is beefier. This is discussed in your owner's manual.

 

[F8L SNK]

My 08 has had the exact same issue. Happened once, pumped the pedal multiple times in a row and have not had the issue again.

I will be bleeding it anyway this weekend to insure I don't have another issue.

 

[08Venom]

I've experienced the rattling on several high performance cars I owned in the past.Never has it resulted in any clutch problems.

 

[twinturbo3150]

I just experienced this for the first time today in my 06 coupe. I was stuck in stop and go traffic and was idleing for about 20 minutes on the the freeway. I went to push in the clutch and it went straight to the floor. I started pumping the clutch and it went stiff again and was able to get it in gear. Once I started moveing it was fine and has not done it since.

 

[2002_Viper_GTS_ACR]

NICE! They STILL havent fixed this issue. I posted about it and others have too. The 06's certainly had this issue, great to see they have improved nothing in this area

Maybe selling our beloved moniker to a company that believes in quality control could better the bread.

Jon

 

[toomanymodz]

My 08 has had the exact same issue. Happened once, pumped the pedal multiple times in a row and have not had the issue again.

I will be bleeding it anyway this weekend to insure I don't have another issue.

Did you get around to bleeding that clutch?

I put my snake up on the rack and bled it. I had my neighbor pump the clutch and hold while I loosened the bleeder screw. I heard a little bit of air come out the first time. To make sure I got all the air out, I did it a total of about 5 times.

I drove it for a few miles and the pedal started to get some additional 'slop' at the top of the stroke and the engagement was fairly close to the floor. Not nearly as bad as before when I couldn't even put it in gear. But still, I'm not 100% satisfied.

How did your ordeal go?

 

[BCBowers]

This is an issue Corvettes have had for years with their hydraulic clutch systems... fluid gets hot, degrades, and pedal gets spongy and will go to the floor on hard shifts. Solution is to bleed the clutch or simply **** out the fluid reservior every few weeks wtih a spare turkey baster and replace.

I agree that it won't fix itself if there's air in the lines... needs to be bled.

 

[silverz06vette]

This is an issue Corvettes have had for years with their hydraulic clutch systems... fluid gets hot, degrades, and pedal gets spongy and will go to the floor on hard shifts. Solution is to bleed the clutch or simply **** out the fluid reservior every few weeks wtih a spare turkey baster and replace.

I agree that it won't fix itself if there's air in the lines... needs to be bled.

Did not really happen in the vettes till it was at the strip or road course. Of course a night of street racing (not legal) could cause the same issues.

The new 08 ACR I just road back from Houston in did not have any clutch issues, but did make the "marbles in the can" noise with the pedal out. This was also "normal" on the C5 Z06s.

 

[CitySnake]

I had the same problem. A one time clutch "softening" in traffic at around 200 miles. Hasn't happened since (900 miles later). My understanding of the problem is the close proximity of the clutch lines to the exhaust (heat and boiling fluid). I know that Chuck Tator is relocating them slightly further from each other. In any event, pumping the clutch pedal to circulate the fluid seems to eliminate the problem when it occurs, though it's not comforting to have your clutch pedal go "limp".

As Bob mentions above, neutral gear rattle has been a fact of life with Vipers over the years. Certain years were more problematic (only with regard to the noise) than others. The '08's are going to be one of those rattling model years. More reason to add some volume to your exhaust.

 

[toomanymodz]

Summit sells various heat tolerant wrapping. I've used some in the past on my big block 540 when wires were very close to the headers. Wonder if that would help. Or perhaps there is a fluid with a higher boiling point?

 

[mjorgensen Woodhouse]

Double wrapping the clutch lines will help a great deal with the heat. Make sure you also zip tie the line as far away from the exhaust as you can, this should eliminate any future issues.

 

[BCBowers]

Both help greatly... use a good high temp brake fluid and wrap all clutch lines. I used ATE superblue in my Z06 and wrapped all lines in DEI cooltape which you can get from places like Summit. I also had my longtubes ceramic coated with black 2000 degree coating for road course duty.

The C6Z came from the factory w/ DOT4 fluid and heat wrapped lines so GM saw it was an issue. Most guys in the vette world who drag race use Ranger's turkey baster method and **** out the fluid from the reservior and replace every week. In the case of the vette you must remove the center section of the exhaust and the tunnel plate to get access to the bleed screw on the slave cylinder, even then it's on top and a PITA to get to. Most guys install a remote bleed line when putting a new clutch in that relocates the bleed screw to the engine bay.... I did and it's a great help.

So in short... flush the fluid and wrap those lines.