hi all, my truck has been scratching/squealing on start up for a while now. not every start just every now and then.

sounds bad, and id like to take care of it. any ideas??? 99 5.4
thankx

 

Same thing happens on mine. Maybe once or twice a month. On a day it screeches once it is likely to happen a second time that same day.

 

Any help on this? seems im not the only one who has experienced this.

it almost seems like something just needs lubed up but ive been told its the flywheel and i dont know much abt that part.

 

This used to happen on the older GMs because they could not build it right the first time so they used shims. The wrong thickness of shims could make the starter do a screach on the flywheel. However.............. Since we don't own GMs........ I would relate this to either a starter issue, or worse.... a cracked flywheel

 

Had my flywheel checked and starter replaced and mine still does it and has for 5 years now. Still a mystery

 

If you guys are saying that the starter grinds and doesn't turn the motor at all and you have to try again to start it, then this used to happen to me all the time. Turned out to be the starter had ground off some of the teeth on the flywheel. I replaced the flywheel when I did a tranny rebuild and the grinding stopped completely. Now it is kinda a PITA to change the flywheel but if that's your problem it should fix it.

Also, I noticed while pulling the tranny and trying to line up the torque converter drain with the inspection port that the motor seems to always come to a stop at the same points. I would crank it just barely and the TC drain would never line up because it would always stop at the same points around the flywheel. I think this is due to the compression in the motor making it come to rest at certain points, but it made me realize that certain points of the flywheel were probably being ground down because its always just those same points. Took out the flywheel, and it had tooth damage all around it at a certain uniform interval.

Good luck,

- Erik

 

x2! I had the same issue, a nasty metal on metal screech that could wake the dead. Bought a new flywheel and had a friend put it in while he had the truck apart and putting in my LT headers. I saved the old one (for a 600yd gong to shoot at) and can get a picture of the teeth being ground down.

 

a pic would be nice if u can post one...

thankx for the responses

 

Here's the part for mine 2000 f150 5.4 4r70w trans


the worn teeth are at the top right (between 1 and 2 o'clock)


and an up close

 

i had the same problem with my flywheel, but what the mechanic found was surprising, he said that i had flung rocks and mud up there and some teeth were broken off. but it could also be if the car is on and you turn the key again.