I just bought my 98 Lariat 4x4 and notice that it shudders a bit when starting into a turn from a dead stop. I don't feel it when I accelerate through a curve or start out straight. Any ideas on what this could be ?

Thanks

 

The limited slip differential often isn't as 'limited' as it needs to be -- which shows up as you've described.

The normal 'fix' is to change the axle lube -- ensuring that the friction modifier is added too.

If this is the situation, it is only irritating, not damaging.

 

Is the 4WD engaged when you notice this shudder?

 

No, 4WD is not engaged. I haven't checked for the shudder in 4WD... yet...

 

What rear end do you have? If you have a limited slip rear end, then I agree with y2k. Change the differential fluid and don't forget the friction modifier. The proper fluid specs and quantity is listed in the back of your Owner's Manual.

 

My 02 F150 7700 with the LS 3.73 rear end has done the same thing since day one. Only on very sharp turns from a stop.

The 4.10 LS rear end in my 87 Ranger was really bad. Changing the fluid solved the problem but I had to change twice a year.

Wouldn't trade the LS for anything though. ALMOST don't need the four wheel drive.

 

My 2000 expy started doing the same thing around 42000 miles. Problem was solved by changing rear end lube and don't forget to add the friction modifier additive. The 75W-140 synthetic oil was hard to find, the local part stores didn't carry it and I had to go to the dealer @ $17.50 a qt.

 

You can get Redline 75w140 for about $8.50 mailorder. I have got some but have not put it in yet.

 

My 98 f-150 is doing the same thing. And I dont know what to do.

 

we ended up having to pretty much replace everything in the back axle. all this happened on a 2000 f-150 supercab lariat 4x4. it started at about 21000 miles and it got really bad at about 45000miles. the ford dealership first replaced the rear seal, and lubed the frictioner. worked for two days and the problem came back and we ended up replacing the guts of the rear axle. that took care of the problem so far. hope this helps, see my post under the same catagory named rear axle problem.

 

I have a 2001 F-150 sc w/ 14,500 miles. This same problem just started on it this week. The dealer said they need to add the friction additive. I still would like to find out exactly what it causing it. I know it's the limited slip but what is it doing? The dealer also said its a common problem on E150 vans. Weird.