When I am at a stoplight I keep the clutch pushed in so I am ready when the light turns green. I wonder if this is bad for the clutch and will cause problems later. The clutch is very easy to push in so that is not a consideration. I just don’t want to wear it out! I would appreciate any advice.
What you are doing can cause premature wear of the throw-out bearing, but I do it if I am first in line to be courteous. If you aren’t first in line, you should have time to press the clutch and shift into gear between the time the light turns green and the time the car in front of you moves, but it means you have to pay attention to the light.
Never keep your foot on the clutch and transmission in gear while stopped at a light. First, it puts additional wear on the throwout bearing. Second, it keeps hydraulic pressure on the master and slave cylinders. Stop with your foot on the brake, transmission in neutral and foot off the clutch. When the light turns green, put your car in gear and proceed.
I’ve heard that in England you have to keep the foot on and in gear at a stop, to pass the driving test.
I take my foot off in neutral not only to save the bearing but also I worry about my foot accidentally slipping off the pedal.
I don’t think you are doing any long term damage. If you know it is a long light I’d recommend sitting in N with the clutch out. That’s been my practice for years and never any clutch problems in all sorts of cars. If the light is short or I think it may change fairly soon I’ll sit with the clutch in sometimes too. It really depends on the situation, and either way I’m not concerned with clutch wear.
I have owned at least one manual trans car for many years; as of now we have two. I have driven some of them to ripe old ages and have never lost a TO bearing. Don’t worry about the bearing. Just make sure that the TO bearing is changed when a new clutch plate is installed. If you have a VW, the TO bearing is inside the transmission and is lubed by the trans fluid and with that setup you can worry even less.
If you want to worry about bearing wear, worry about your alternator bearings. These are similar in design with factory installed lube and rubber seals to keep the lube in and the dirt out. The alternator bearings are used continuously while the engine is running. The TO bearing is used intermittently and relatively little compared to alternator bearings.
Wouldn’t the forces on a throwout bearing while the clutch is depressed make it unfair to compare it to the bearings in an alternator?
No, there is a lot of tension on an alternator belt.
Ball bearing thrust bearings actually need load on them to make sure the balls roll instead of skid. That’s why you should never rest your foot on a clutch pedal while the clutch is engaged, you are putting a small amount of load on the bearing but not enough to make the balls roll instead of skid.
When you completely disengage the clutch, there is enough load on the bearing that ball skidding does not occur.
This is hard on the throwout bearing, and can wear it out prematurely. With your clutch pedal pushed in the bearing is fully loaded with all the force of the pressure plate assembly’s spring load, that same load the clamps the clutch plate between the flywheel and the pressure plate with enough force to move your vehicle forward. With the clutch pedal totally released, the throwout bearing is fully unloaded.
Fully loaded vs. no load. Fully loaded will always wear faster.
This is One reason why autos experience fewer problems than manuals in the hands of some.
The TO bearing does not see the full force of the clutch spring load because there is a mechanical advantage in the lever setup inside the clutch. Judging by eye from an illustration in one of my repair manuals, it looks like approx 4:1.