Engine/Transmission (1998.5 - 2002) Very jittery launches

[pdxkevinc]

Folks,



I can't find anything in the FAQ on this one. I have a 98. 5 24v 4x4 manual. Over the last few thousand miles if I'm towing my 5th wheel I get really jittery launches. I've been towing the same trailor for 6 years and in all those years I can usually slowly let out the clutch and get moving without even touching the accelerator. Now, I get this jerking, slamming situation. What should I suspect? Clutch? I have a Luk clutch with less than 24K mi on it so that seems wrong.

 

[PC12Driver]

Which Luk? Was it a higher HP version?

 

[pdxkevinc]

ugh, now I feel stupid... I don't know. If it is, would that be suspect?

 

[PC12Driver]

Could be... The higher hp clutches can be a bit more grabby, and that combined with the axle wrap from our 4x4's leaf springs and lift blocks can get things hopping pretty good. Clutch starts to grab, axle wraps up then unloads, truck bounces, which in turn bounces driver and clutch leg, which causes the clutch to grab and release, which loads and unloads the leaf springs, lather, rinse, repeat.



Other than that, how's the clutch pedal action feel? Is it smooth to the floor and back?

 

[pdxkevinc]

PC12Driver,



Thanks for the reply, I really appreciate it. I have done some more testing. I went up to a pretty steep hill last night and on pavement, unloaded, in granny AND reverse, I get the jerking... slight, but you can tell it would be exaggerated by load. And I do notice the clutch travel has some unpredictable points... sort of sticky if you will... is this a simple lube issue? I thought all that was hydrolic? no ?

 

[PC12Driver]

Sticky clutch travel could be the clutch master and/or slave cylinder (the hydraulic parts) or improper lubrication of the throwout bearing on the input shaft (that slides back and forth when you work the clutch).



And yeah, trailers will aggrivate the hoppy-hoppy situation. When did you first notice this problem? Who did your clutch?

 

[nabowers]

i have a friend that is running with the luk clutch. he has had the same hoppin since day one. changed the hydrolics and still does it. called luk and they said that is fairly normal. other than that the clutch holds great. i work for a performance corvette shop, Lingenelter performance engineering, and we install luk clutches, and they different than any other clutch on the market, but they hold up to massive amounts of power.



nathan

 

[pdxkevinc]

thanks for the info, Nathan. For me, a smooth lauch is about the most important thing. I cannot stand all the slamming of the kingpin and heads jerking around in the cab ... sucks...