At 140K miles had clutch replaced. Started slipping 20K miles later. Found replacement at 140K was installed incorrectly. I then personally replaced clutch again. Truck shifts much better, however, after truck warms up clutch slips again. Less after dropping it down one gear. Can it be my transmission - NV1500?
What technique are you using to determine that the clutch is slipping or what symptom are you seeing that leads you to believe that the clutch is slipping?
It sounds like the clutch is slipping if it stops when you go to a lower gear, however the linkage might just be too tight. It might be keeping it from engaging completely. Not good for the clutch.
Put the car in 4th gear,let out the clutch,the car should die,if it doesn’t the clutch is slipping.
Elly, your post make me say, what?
Say what?
Well here’s what I tried to say. It sounds (to me) that the clutch is slipping if it stops doing whatever it does when you shift to a lower gear. However, the clutch might not be fully engaging because of no clearance between the clutch release arm and the throwout bearing. In other words it might need adjusting. Does that make more sense?
Why would shifting to a lower gear (like from 4 to 3) reduce clutch slippage? The mechanical advantage provided by the transmission is greater in the lower gear which would promote clutch slippage not reduce it.
There is no adjustment possible in the area you speak of. If we have a not fully engaging clutch it is from a broken or misaligned part,not a part out of adjustment.
“The mechanical advantage provided by the transmission is greater in the lower gear which would promote clutch slippage not reduce it.”
Noooooooooooooooooooo. Sorry,oldschool, but you have it bass ackwards. Mechanical advantage makes it far more likely to slip in HIGHER gears.
The higher you go up in the gear range the closer you move to a 1 to 1 ratio. Lower gears (as in first gear) provide more mechanical advantage. You use this mechanical advantage to get the vehicle moving from a start after you are moving you need less mechanical advantage.
I pulled up a data sheet on a 2009 corvette 1st gear ratio is 2.97 to 1 moving to 3rd gear ratio of 1.43 to 1 and ending up in 6th gear with .57 to one. In fact 4th gear is direct 1 to 1.
Are we making a mistake confusing higher as in higher numericaly or higher in range? Do you call 1st gear high gear or low gear? I call 1st gear low gear, the gear with the greatest mechanical addvantage.
As I wrote earlier in the thread I always picked 4th gear to make my stationary clutch slippage tests, but why after the vehicle is moving and in a 1 to 1 hookup would it be more prone to slipping than in a gear providing some mechanical advantage (as in the Corvette I cited with the 1 to 1 4th gear and the 1.43 to 1 3rd gear) I do wonder? Perhaps because less torque is transmitted in the 3rd gear and it doesn’t require so much clutch clamping power to prevent slipping? But that idea also sounds backwards.Oh well I will sleep on it,perhaps it comes to me in a dream.
Well, Oldschool, if you don’t know why shifting to a lower gear would reduce the slippage, then I don’t know what to tell you. Why did you reccomend using 4th gear, why not first gear, hu? Also many clutch linkages are adjustible (probably all) whether it be by moving the slave cylinder, or shortening the linkage. You need a little free play in the linkage. This Quote of your’s is getting close to the fact. "Perhaps because less torque is transmitted in the 3rd gear and it doesn’t require so much clutch clamping power to prevent slipping? "
"You use this mechanical advantage to get the vehicle moving from a start after you are moving you need less mechanical advantage."
This advantage applies to the clutch also. It is much easier to move a vehicle in a lower gear, thus it is easier on the clutch.
CLEAR?
The mechanical advantage is with respect to the front end of the transmission, or the clutch / engine. In lower gears, e.g. first or second, the transmission provides more mechanical advantage, effectively making it easier for the engine to move the car, by REDUCING the torque required by the engine. That torque is transmitted through the clutch. It’s that torque that is multiplied by the mechanical advantage of the transmission.
In 4th gear in your example, since this is a 1:1 ratio there is no mechanical advantage or torque multiplication, so the engine would have to provide torque with no mechanical advantage, all of it transferred through the clutch.
Well, fathersupreme, do we have a slipping clutch or don’t we?
Does anyone know if the clutch (linkage) on this S-10 is adjustible??