I can't figure out why heat would cause it to stiffen up, you're not using the clutch when you're staying in one gear so where's the heat coming from.. And if it's from lack of heat, why doesn't it feel like that when you first start it up in the mornings? Edited by: Camstyn
I have never seen a 6 speed truck, I dont know of any troubles directly relating to that problem. I dont know if heat is the trouble or not, the coolest operating condition for the trans is at a steady speed. Not much heat build up going down the highway. The ZF6 comes with Transynd in it from the factory so you wont upgrade fluid by much. Is it only stiff for the first few pumps or just one pump or.....?
Just as long as don't over push your truck you will be all right. I cracked my fly wheel on my other truck because I left the 60 hp tune in one night pulling a 30 ft trailer with 15 rolls of hay and the bobcat on the back. The clutch was slipping but I never backed off till I got home. But if it ever gets that way you will literally have to stand on the clutch pedal to get it to push in.
Sorry to drag a thread back from the dead, but mine's in the dealership as of today for them to chase this problem. It's stiff for the first hit after any siginificant distance, and the first several hits after towing for a serious distance.
I just got back from a California round trip (Cali's 1200 miles each way for me) and if I ran an entire tank of fuel nonstop, the pedal would get so stiff that it'd lift me out of the seat pushing it in. I'm not a real big guy (160lb) but what really worried me on that is that if my wife drives it (she does occasionally on the roadtrips) and she runs a tank, she won't be able to put the clutch in at all--she'll just have to drag it down against the engine till it stalls on the ramp. Just to put some numbers to it, my '03 has over 27k on it now... and I've had it 12.5 months. About half of that has been towing, but only about a 6-7k pound trailer.
My fear is that a friend has had a stiff clutch be a sign of a failing clutch/flywheel, but his was out of warranty--I don't want a known problem that showed up under warranty, screwing me out of $2k+ when it fully blows up.
Also, the dealer tried pulling some shady crap about a warped front brake rotor--GM Customer Care says 3/36 on the rotors (pads are a wear item) and the dealer tried to tell me that the brakes are 2/24. They've got a service request number, an extension at GM Customer Care, etc., and they're saying "well, we can cover it once, but after that..." Apparently, I should find a different dealership in the northern-Denver area.
Edit: Just as an FYI, my truck is a 2WD cab/chassis, box stock. Closest it's got to modifications are a flatbed, a toolbox, and a better hitch--we'll see what the dealer says about my tendencies to "abuse" it in 100% stock form.Edited by: ScottRS
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