Hoping you guys might be able to help

Got a few things going on, and I'm a little confused. First, I have a '76 F-150 2wd with a 9" semi-floating rear end

A few months ago I started to hear what sounded like a wheel bearing roar. The truck isn't an every day driver, so I've been kind of ignoring it. About a month ago, I got a real bad vibration coming through the box, so much so, that I couldn't take it over about 30 mph. The rear tires were 20+ years old (and snow tires) so I figured it was probably time for a new set. The tire shop guy said that the tread had separated on at least one of the rear tires, so I got a new set of rear tires.

The truck still had the bearing roar though, so today, I put the whole truck up on jack stands and took a look. In spinning the front wheels, I neither felt nor heard anything odd, so I put the truck in gear and let the rears spin free. I thought I could kind of hear something, kinda hard to tell though (could have been just the emblems rattling around in the hub caps) but I did notice that the drivers side rear tire looked to be wobbling pretty good (lug nuts tight) I know that every now and again you get a bad tire, so I looked at the brake drum, and saw that it looked to be wobbling pretty good too. I figured that I might have bad rear wheel bearings, so I shut the truck down, and took a large pry bar under the wheel, and found that I could move the whole wheel assembly up and down, what felt like about an 1/8 or 1/4 inch, on both sides. I pulled the wheels off, and found that I still had the movement, by just grabbing the axle shaft. I pulled the axle shafts, expecting the bearings to be shot, but they looked perfect, no pitting, damage or discoloration to the bearings or races. What the heck?

Has anyone ever heard of an axle shaft bending in one of these? Also, I don't know if it's normal, but if I grab the wheel and spin it in either direction, there is about an 1/8 of a turn of free play, before you hear the clank, and the other wheel spins (every time I put the truck in gear, I get the same sounding clank, but I've checked the u-joints several times, and they are tight)

Sorry for sounding a little green, but while I've messed around a little with heavy truck (semi) rear ends, I've never messed with an automotive one, and just don't know what's normal on this.

Any help or input would be greatly appreciated

 

I cant be of much help but I will add that I have owned a '73 and a '79 F100 and both clanked when you put them in gear, reverse more so than forward iirc. both were automatics. I have owned two with manual transmissions also and never noticed it, I suppose because of the action of easing out on the clutch as opposed to an autos abrupt shift.

 

Mine's an auto as well. Kind of comforting that the clanking might be kind of normal for these. I've never owned an old Ford truck before (or a newer one for that matter) so I was unsure if I was looking at the some kind of failure in the center section as well. Thanks man

 

If you can move the wheel/axle up and down, then it is highly likely the bearings are bad. The bearings may look okay but the real test is whether the bearing can support the load... and I understand you did a run test with the wheel off the ground... therefore the bearings are unloaded and make little, if any, noticeable noise. I don't suppose ya cleaned out the bearings and examined them dry? Did you wiggle the bearing's outer cage to check for play?

Do you have a receiver hitch? When I insert the ball into the receiver, it has a little bit of play and clanks whenever I accelerate from a dead stop.

 

I'll bet $ the "clunk" he is refering to is the one you experience as soon as you put the auto shifter into reverse to back out of your driveway, doesnt matter if your holding the brakes or not, you still get a "clunk", at least my 2 dents with C6s did.

 

Sorry it took me a couple days to get back to you, been super busy with a shopping list of projects around here. I haven't pulled the bearings off the axle shafts yet, as it looks like I'll need a press to do that (will probably run the shafts up to the local machine shop to be removed and installed) but I did notice quite a bit of play in the bearing cage. I didn't think much of it though, since I didn't see any visible damage to the rollers. Sounds like it's time for some new bearings, either way, as long as I've got it apart, it sure isn't going to hurt anything. Do you know if it's necessary to replace the bearing race in the axle tube at the same time on these?

No receiver hitch on mine, just have the ball mounted in the bumper. Sounds like the other poster was saying his did the same thing, which kinda puts my mind at ease a little. Don't really want to spend a fortune to get her back on the road.

 

My truck has the C6 as well. It's cool if it's normal, I was just worried I had more going wrong with the truck. I wasn't really thrilled with the idea of tearing into the center section, until I get the money for the locker I want.

 

Apparently, I stand corrected when I said it couldn't hurt to change out the wheel bearings, as those little suckers cost $120.00 per bearing to do, which doesn't include the wheel seals at $13.00 a piece.... all that is just a little out of my price range right now

If that wasn't bad enough, I'm having a heck of time finding a shop that can/will remove the bearings off the axle shafts so I can at least replace the wheel seals, being that it's been apart now. Last place I went to suggested that I try the Ford dealership, and mentioned that the collars on the shafts above the bearings were one time use, and would need to be replaced when servicing the seals. Does this sound right?

 

What the hell bearings are you buying? Timken Set 20 bearings run about $19.99 each around here. Taking the old bearings off the axle is easy (hammer and chisel) as is removing the race in the axle housing.

Getting the new bearings pressed on may be a little tricky if you can't find a machine shop to do that but any good machine shop should be able to do it. Otherwise get a long piece if iron pipe that JUST FITS OVER THE AXLE SHAFT and rests on the inner bearing race, not on the outer race nor on the bearing itself and smack on the pipe with a 3 pound sledge.

 

Where are you getting those prices from? I got my last set for $26.00 from o-rileys

 

Yeah you're 9" bearings should be relatively cheap for a set of timkens. The ones that are in my dana 60 were $28 a pop for skf's.

Something to check next time would be to see if your preload is okay.

Poison oil's self press is a good idea, other wise use a brass drift and put the races in.

 

Farm and Fleet. $19.00. $26.00. Not much difference.

 

Prices were from the local auto parts store in town. I guess the trick of it was that my truck has the 3750# rear axle. I checked LMC as well, and found they were the same price through them. I see that the other axles use a reasonably priced bearing, but not mine apparently.