Rear end clanking...

[Effieman]

Had rear end noise in my 98 4X4. U joints seemed fine, but I thought there was a lot of slop in the driveshaft rotation. When jacked up it would clank around 3 or 4 times per tire revolution (3.73 gear). Any way to narrow down what may be wrong without tearing anything apart?
It is also limited slip if that makes any difference.

 

[RonD]

If u-joints, or slip joint, are not the issue then you will need to loosen, drain, and then remove cover, to see whats loose

Ford Ranger 8.8" 3.73 L/S axles are usually a safe bet used, 1993-2009 are the same
car-part.com is a good place to look in local area to get a price of a used axle, just wrench work to swap

Then check price to repair what you have, with new L/S clutches, you need a bit of knowledge to re-shim a rear axle, there are videos

 

[sgtsandman]

What transmission do you have and how long have you had the truck?

If it’s a manual, because of the way the transmission works, you will get some clanking in the rear end as the differential loads and unloads with the back lash. If automatic, then you may have a problem since the transmission is almost always applying pressure to the differential.

The reason I ask you how long you’ve had the truck is if it hasn’t been long and you aren’t used to a manual transmission truck, the clanking can be unnerving but there is nothing wrong.

 

[Effieman]

sgtsandman: I have the manual transmission. I bought the truck in January of 1998 with 12 miles on it. It now has 329K.
I originally thought it was the U-joint because it made the same clunk as when they did go bad. I recently was driving with the windows rolled down, and I thought I had a rod knock, till I looked closer...

 

[sgtsandman]

sgtsandman: I have the manual transmission. I bought the truck in January of 1998 with 12 miles on it. It now has 329K.
I originally thought it was the U-joint because it made the same clunk as when they did go bad. I recently was driving with the windows rolled down, and I thought I had a rod knock, till I looked closer...

This helps us help you and fills in some blanks. You had the truck for a number of years. So know what to expect. We get a lot of new, in experienced owners. So, I wanted to weed that out as a possibility.

 

[Dirtman]

I'd pull the driveshaft out, inspect it further especially the slip joint for slop. Fords are known for driveshaft slip joints wearing and clunking. While the shaft is out you'll get a better idea how much slop is in the pinion as well. But with 329k miles chances are the differential is just pretty worn out so if the drive shaft is fine time to pull the cover and have a look inside like Ron suggested. The clutches in the limited slip are definitely dead with that mileage.

 

[scotts90ranger]

If it's clunking that much per tire rotation either there's ring gear issues or something wonky...

Personally with a third of a million miles on a limited slip I would suspect spider gear wear... I've seen it first hand, when I got my '00 Explorer the spiders were nearly rounded off and only caught occasionally... but that's a 5000 pound vehicle with a V8 and at least one of the previous owners abused the heck out of it since also the transmission was destroyed and the hitch is bent down somehow?

 

[cbxer55]

The spider gears in my Rangers 7.5 had noticeable wear at 178,000. Had my friend Rick change them at the time he was putting in the 4.10 gears.