My F-250 just got back from my local 4Xshop.. I had them replace the thunking front sway-bar bushings/links and change the rear diff fluid.

The front-end thunking and rattling is gone but...

The truck squeaks upon stopping now and shakes and shudders over 50mph-ish

It does have a limited slip and they have on the paperwork that they used 1 unit (donno how much they are calling a "unit") of equatorque and 4 units of synthetic gear oil. (17.99 a unit)

After doing forum research, my initial thought is that the clutch packs are gripping and that they did not use enough friction modifier. but then I worry that they used too much.

I am going out to check the fluid level (hope they put it in) then do some figure 8's and some over-50mph driving (since it's 4:30 am here, this may be a bit difficult..)

Any thoughts from you guys? Especially thoughts on too-much modifier...

Thanks!!
Wizbang

1999 F350 PSD XLT
2002 F250 V10 Lariat

 

ok.. the squeak seems to be from the front and directly corresponds with the rotation of the tires when stopping. Possibly a hung break caliper but sorta sounds more like squished and ground rubber than brakes.. The front seems to have a muted hum while driving too.. maybe bad needle bearings up in the front hub(s)? all 3 front axle connections spin freely, U joints look fine.

The shake in the back may just be wheel balance, I have to check the air pressure too. Unfortunately I've only driven the 250 since Tuesday so I don't know the original usual-noises/feelings of the truck to make a good comparison. It may have been doing all these things before the work at the shop.

I went with Power-slot cryogenically hardened rotors and hawk brake pads on the F350, stops on a dime now.. I'll have to check them since I have not looked at them since they were installed. Looks like it's next of the list for the F250, along with a balance/rotation, and bearings check.

anyone,, any thoughts?

By the way,, the PSD gets 12.2mpg and the V10 gets 9.6mpg with the exact same load. (trailer and Jeep CJ7 on it) but the V10 seems to have more pep.

Thanks!!
Wizbang

1999 F350 PSD XLT 67,000m
2002 F250 V10 Lariat 77,000m

 

Did they put any lube on the center swaybar bushings?,ford has a bushing lube for that.

 

donno... I returned to the shop 1/2 hour after I left, and told them I think the swaybar squeaks, they said they had to "lube those things like crazy just to get them on, it cant be what's squeaking"

they used a polypropo-something bushing kit, not ford parts.. sure did stop the klunking.. and today the squeak is much less so maybe i need to drive it for a couple of days..

 

might check steering components (sway bar, stabilizer, etc). typical problems from loose ends around there.