when I take off from a stop i have a little bit of a vibration in my rear end, but its only when im turning, when i go straight from a stop its donst happen. also at highway speeds is sounds like a whining sound coming from the rear end, the truck has 45000 miles on the od, it is a 2004 fx4. i was just wondering if anyone else had this problem or new what it was?

 

Question about the whinning noise. Can the sound be altered or rather stopped by using the accelerator? Is it present on accel or decel or on coast? All are signs of bearings going bad on the pinion. This is the shaft that sticks out of the rear end that the driveshaft connects to. Although the job isn't that hard to do, special tools are required upon reassemble for proper clearances of ring and pinion. Vibration could be from this, but I would also check U-joints for that concern.

 

Well my first thoguht would be a U-Joint. Have you checked those?

 

you can hear it when on accel, once you get to highway speeds, not on decell, it doesnt make noise, or i cant hear it. i havent checked the u joints or anything else, besids the fluid in the rear end.

 

you cant hear the whining on coast either.

 

Could also be the rear end clutches slipping. Mine did the same thing on acceleration in corners. Never really noticed a whine but then ago the damn radio is usually turned up. Dealer fixed mine by adding a modifier to the rear end fluid.

 

are the inside of your rear rims coated with with grease or anything? it could be the axle seal, mine needs to be repaired and it caused similar problems

 

This sounds exactly like the problem my F-250 was having and the clutches turned out to be the problem. Somehow they had gotten too hot and warped and were chattering everytime I went around a corner.

 

no there is not any frease in the rim just the usual break dust and dirt. i am going to take it to the shop this week, i am getting tired of the whining. ill let you know how it turns out.

 

feel your pain same truck and year 44561 miles same problem just took it to the dealer they said problems with the clutch's in rear end. did differential fluid change and added some sort of special additive said will take up to 500 miles to break in almost up to the 500 mile break in still having vibration will keep you updated on my progress seems you have the same problem. my addvice save yourself the money i did not change the fluid yourself and buy the additive from ford. i spent 150 at the dealer 75 in materials and 75 for labor i could have done myself.