I've asked a couple questions about this on the superduty forum and havent had much luck. To make a long story short, my rear end went out 2 days after I replaced my clutch and now the rear ends out again 2 days after it was fixed. I'm not gonna try to go into it the thing again-i'm just gonna get a whole rear end for it. So I've got 2 questions- 1. Is the pinion yoke the same on all 99-04 single wheel trucks no matter the wheelbase or driveshaft?, and 2. Do yall think that any type of driveshaft problem could cause a pinion bearing failure- and fast too about 2 days. Thanks.

 

I don't know the answer to any of those questions other than to say that a bad driveshaft that would kill a pinion bearing would shake the truck enough to alert you of any trouble within a block or two. You would not have driven it far without bringing it right back to investigate.

 

What went out on your rear end the first time and what did you replace? If anything is changed in the rear end, such as bearing wise, the entire thing must be re-checked for backlash, bearing preload, etc etc. Did you install a new crush collar? I bad drive shaft could cause it but you would feel it very badly and not drive it because it would feel like it was going to exploded at any second and IMO that would be VERY off balance.

 

there are two different pinions, depending on what rearend you have. some trucks have a spicer some have a dana.

 

The first time I replaced all 4 bearings 2 pinion 2 carrier, and yes i set the gears back up. Pinion depth was good, backlash was .012", and the pattern looked good. New crush sleeve. Seemed fine for 2 days.

 

did u notice anything out of the ordinary after the rear end was complelted? It sounds like the driveshaft is way out of balance. Im assuming you checked the bearing preload on the pinion correct since you said you did set the gears back up. Backlash is good. Check to insure your vent tube is not plugged up.

 

Once I fixed it, it drove fine for 2 days, about 150 miles. Bearing preload was right at 20 inch pounds. There were no vibrations at all during that time, until it started vibrating again monday night and the pinion was loose again. It didnt leak from anywhere, pinion or cover.

 

Call the guys at Randy's ring and pinion. Talk to Drew. Very very knowledgable. When I was talking with them about my 99 he said there are a few that have a different pinion. Not very common at all, but they are out there. Also, did you change the inner pinion race? When I did my gears recently I noticed the the OEM bearing and the new bearing had different taper angles to them, so I had to knock out and replace the inner pinion race too. That was the biggest pain of the whole ordeal.

 

Yeah, all new bearings and races, which reminds me, anyone know of where to get race and seal drivers that are big enough for these axles? I just used a brass punch, but it would have been a lot easier with a driver.

 

How much did it cost you by chance? I put in about 600 or 800 the first time I did mine and it bbqed itself within 4 months of hard pull. I drove it the 40 miles to Reno stinking, smoking and grinding all the way. I wasnt going to stay where the Aliens could pick me up. Cost at the rearend shop was 1026.54, 1 night at the hotel and away I went.

 

The bearings cost me about 200 bucks. I'm thinkin now that the carrier must be cracked or something and I didnt see it when I had it apart. What I cant figure out though is that the only symptoms are the loose pinion and the vibration. Last night I tried to get it to break just to see what it was since I'm gettin another rear end to put in. Its not leaking, making noise, or smoking. I dropped the clutch a few times and did some hard pulls, but it wouldnt go ahead and break. The vibration gets a little worse, but it wont lock up or break. It cant be the driveshaft because after I got it fixed it drove fine for almost 200 miles with no vibration before it went out again.

 

Here's a longshot, but did you recently lift the truck, and point the pinion upward substantially? The thought would be poor pinion lubrication.

 

nah, stock suspension, but thanks