A few months ago I replaced the rear axle seals and bearings, and the entire rear brake system.

Right away I noticed a vibration that starts in around 55 mph. I thought it was the tires/rims I put on at the same time, but after getting them balanced I still had it. Life got busy and I put off doing anything with it till a couple weeks ago when I noticed my new CV axle on the passenger side had blown the boot off somehow and the clamp was gone. So I squirted a bunch of greese in there and grabbed a couple 4" hose clamps and put them together to hold it one there till I could get a replacement. I really though that calmed it down, but after replacing the axle tonight, thevibration is still there.

So what might I have done wrong with the rearend to pick up this vibration? It gets worse the faster you go, 65 is too fast at this point. Should I try to get the tires balanced again? I'm really getting fustrated with this truck, I've sunk a ton of time and $$ in it now and I swear as soon as I get on thing fixed, something else pops loose.

 

Noticed today a full tank of gas might be the culprit for it feeling better once in a while. Maybe my bearings went in wrong? Also, the gears fell out when I was messing with it. If they didn't go back exactly the same way, would that make it vibrate? I used Royal Purple 75w-140.

 

I have the same problem. It feels as if my tires have GIGANTIC tread and it makes a lot of road noise. The first dealership I took it to in NM last week told me it was the ringer and pinion and that my rear end needed to be overhauled. THAT DIDN'T MAKE IT GO AWAY. I took it to a buddy of mine that works at a Ford dealership here in TX and he swapped out the driveshaft. WA-LA!!! The vibration was gone. Now I have to figure out how I'm gonna pay for this work and a new driveshaft. Anyways, let me know how it goes. Good luck!!

 

Thanks, I will check my driveshaft again. Better this time.

Can someone tell me how to check the ring and pinion?

 

When was the last time you serviced your rear differential? I'm no mechanic but I know it's definately not a good thing if theres metal shavings in it. Is the vibration the only thing you feel? I've heard that a winding noise coming from the rearend usually means you need new ring and pinion gears or new bearings.

 

I am not real familiar with these diffs but what do you mean the gears fell out? Does the oil you have in it contain the additive that ford diffs require? The best way to check your diff is to first check for metal in the oil. You may want to check your park brake cables and be sure one is not siezed and also check your rear brakes. Are these drums or disc? If they are drum it is possible to have a shoe out of alignment. Unlikely but possible. Also does it do it only under power or while coasting? All these questions need to be answered. It may also be a bad ujoint. Always start with the most simple checks. Tire balancing is usually the culprit. There is some type of bead or sand you can get put in your tires for balancing as well. Mostly people with Duallys do this because of mud getting stuck between the wheels. It will automaticly balance the tires as you drive.

 

When the axles were out, the spider gears fell out of their place. I don't know if they were rotated or not.

I used Royal Purple Max-Gear High Performance Automotive Gear Oil with limited slip additive. 75w-140.

I do not have a limited slip.

The rear brakes are new disc with the parking brake being drum. I do have a seized/dry cable. The brakes were set as loose as possible and have not been applied since the new brakes were added. The discs, calipers, pads/shoes, and parking brake asseblies are all new. Along with the axle seals and bearings. I plan to get the cable eventually, but can't right now. If it's brakes, my thoughts were the vibration would change as the brakes heated up.


It does it with the speed. It starts to show up just under 55 but it's hardly noticable there, after 55 it gets worse as speed increases, either under power or not.


I already balanced the tires once and nothing changed.

I've been under it and shook/twisted driveline and it felt ok.

 

I'm finally getting that new driveshaft. I'll let you know for SURE tomorrow if the vibration goes away.

 

I had that problem before too.

Scenario: During warm weather, I service the rear diff on my truck (was leaking at the seal) I also inspect the U-Joints and determine they need work but I have half a year or so before I really need to concern myself about it.

Later, I had new tires put on the truck. The day I pick it up, I get vibrations around 50-55 mph. I go back and forth with the garage saying they didn't balance the tires right and maybe they need to force balance them again. I even get the garage to send a tech on a ride with me. The tech says the drive shaft is out of alignment. "Yah...right...you guys put new tires on and suddenly this happens? "

So weeks go by until one day on the way to work I hear a bang and then violent vibration. Turns out the rear u-joint snapped, the yoke on the drive shaft slammed onto the flange bolts on the rear diff, and I caused some morning drivers to become enraged.

Check your u-joints on both ends of the drive shaft less you upset fellow commuters.

 

Sorry it took so long to reply. Anyways, the driveshaft was replaced and the road noise and vibration is GONE!! Thank God! Did you get yours taken care of?

 

I have an 04 extra/cab 4wd FX4.
When you drove the truck when its cold in the
morning I could go to 90 mph and nothing.
The minute I hooked up a a small trailer and put on my dirtbikes and drove about 10 miles at 70mph it started vibrating,the hole dash and everything really bad.
When I slowed down to 60 mph it went away.
I pulled the drive shaft out and took it to a driveline place to check the balance,I have visteon staked in u joints and a antivibration ring mounted in rubber on the slip yoke.
The driveline guy spun it up and that ring went crazy.
He took a hacksaw and cut it off and spun it up again and no more vibration.
I put it back in the truck and hooked up the trailer and drove ot for 2 hours at 75 mph with no more problems.
So I would try cutting that ring off before I spend $600 on a new shaft.
Its free and it took 15 minutes.
If you can move that ring with your fingers think how far it will move when driving??

 

I had a similar problem and it turned out to be a bad emergency break release. It would start shaking and the dash would vibrate like a blew a tire at high speed. The mechs said I needed new front rotors....$1200 dollars later, it was just a bad parking break cable.

 

I had this same problem when I changed rear end oil and greased the slip yolk to fix the tsb probs in my 04 xlt spent days messin with it. I had marked the driveshaft as I took it out, eventually after days I started to reinstall the driveshaft in different positions related to the marks I have put on it(slip yolk only) stayed the same on the rearend. after couple days of moving that thing finally got it 3 splines from the mark I had put on it. before this all was great no vibrations or nothing I had never seen this before. I thought a driveshaft was balanced and could put it back anyway you could get it in.