I'm a rookie so don't expect that I know anything. ;D I've been doing brakes on light trucks for may years. This is my first attempt on my '90 3/4 ton that I've owned for 2 years now. With 130,000 I've decided to do my brakes. But after the second night with the truck on jack stands I've decided I need help.

I've installed a napa rotor (TruStop 4885843) and it seems to be to thick(only replacing one). It's bottoming out on the caliber mounts(I'm not sure of the proper name). I've tourqed it to the hub to make sure its properly seated. Yet it sits right up tight to the caliper mounts and dusk cover. The hub needs to go on another 1/16 to 1/8 of an inch but it can't.

Also when it comes to installing the pads. I've forced the caliper piston back into the caliper as far as it will go(not quite flush). Yet there is not enough room to fit the rotor and the new pads. I need another 3/16 or better. Are these calipers reusable or do I have to buy a new one?

I was hoping to get some input before I go to all the work to remove the rotor and take it to the parts store.

Thank you,
Brian Cain

 

By the sounds of things you have the wrng sized rotor. If you look at the rotor compared tot he old one what does the off set look like? It sounds a bit different from the way you desribe it. The calipers should slide right over the rotor so i am wondering if the rotor is too thick taking me back to my original conclusion that the rotor is not for that truck.

I would make sure they gave you the right rotor for your truck before going any farther and possibly damaging something.


Good Luck


Jason

 

The new rotor is a thicker than the old ones. I just assumed the old ones where worn down. But after thinking about it I don't think they could be that worn. The sticker inside the door says I have a 4500lb front axle. But I wonder if I need a rotor for the lighter axle. I did a serch on Napaonline and the rotor I have is not offered for '89 and my truck has a build date of 8/89 but is titles as a 90. I'm off the the parts store, with old rotor to figure this out.

Thank You,

 

Wagner wants the casting no. of the hub on 4.5m axles.
There are two different rotors for it(4.5m)

 

It seems there is a lot of descrepancy on brake parts for the first gens, I dont know about the laters. The diesel models have a 4500 lb front axle rating, some have found that asking for 1 ton parts gets them the right parts. my friend is still having trouble locating rear drums for the same. they keep getting non floating drums that are smaller than a 1/2 ton trucks. Keep trying!!!!. All the parts, calipers etc,will slide on eaisly if the pads are set back enough. if you change the wheel bearings the parts store will be able to match them by the old # on your bearings and races. if not a bearing house will. Good luck.
Apache

 

I agree with Steve, sounds like the wrong rotor, some confusion with the front brakes/steering part #'s. I've got two sets of inner hub seals, one from NAPA and one from Parts Source, both swear they are the right ones but are of obvious different sizes...I will let them both know which seals turn out to be the correct part #.

 

I took the old rotor to napa. The one they gave me was close but it had a little to much offset and the rotor itself was to thick. There is another rotor option that calls for a certain casting number. I wan't able to find this casting number, but I'm assuming this is the one I need. No body in the area had one of these on hand so I had to order one. It will be on Monday hopefully this will will the right one.

Good think I didn't need the truck this weekend. :

Thank you,
Brian