Thinking
98 F150 5.4L E40D/4R100
Joined: Nov 2006
Posts: 28,523
Likes: 7,633
From: MI
Thread Starter
Senior Member
Joined: Jul 2010
Posts: 8,544
Likes: 2,552
From: Alaska
If decide to go with another assy from a wrecking yard, if you want a limited slip, ask for a S829 (A,B,or D) would be the correct replacement for you S828 axle. Both 828 and 829 are 8.8, same year assy, just non-LS vs LS.
I ran the Cali yards and there are a lot of them. Drum or disc brakes makes a difference, so just tell them you want a 2000 F150, 8.8 and want the S829(X) differential. Looks like the pricing runs from about 350 up. .
I ran the Cali yards and there are a lot of them. Drum or disc brakes makes a difference, so just tell them you want a 2000 F150, 8.8 and want the S829(X) differential. Looks like the pricing runs from about 350 up. .
98 F150 5.4L E40D/4R100
Joined: Nov 2006
Posts: 28,523
Likes: 7,633
From: MI
Price will vary by miles usually. I'd look for 150,000 miles max. They are good assemblies normally. Axle shafts and bearings last from 200-225,000 miles if oil is kept in them. Those aren't difficult to replace and about 1/2 a day to get the job done correctly.
Now an XLT in Colorado
Joined: Aug 2016
Posts: 5,977
Likes: 3,171
From: Colorado
Easy to miss with the number of posts you've made.
It's not.
Yep.
Not really. Drain it out and put the old back in. Save the new for the replacement rear end.
You can still eat with a chipped tooth, right? 
The damage isn't totally interfering with the operation of the rear end.
If more if it breaks off, then yes, it could get caught up in the ring gear, trash the pinion gear, and lock up the rear end while driving. It could also just fall to the bottom of the pumpkin like that one obviously did... A number of scenarios.
I didn't see any other noticeable damage other than the bad wear pattern.
Just missing from what I see.
This didn't happen in 3000 miles of driving it was poorly set IP and poorly maintained for much longer than that.
If it's not limited slip, then why is friction modifier necessary in the rear differential ?
Wow, that spider gear is busted?
Damn! What a waste of new oil and all in a broken rear diff.
If the spider gear is broken why is the vehicle still driveable ?
The damage isn't totally interfering with the operation of the rear end.
If that spider gear breaks off will it get caught somewhere?
In the ring gear?
In the ring gear?
Can you circle some more problems in the pics provided?
Just missing from what I see.
This didn't happen in 3000 miles of driving it was poorly set IP and poorly maintained for much longer than that.
Last edited by OhioLariat; May 7, 2022 at 06:38 PM.
Now an XLT in Colorado
Joined: Aug 2016
Posts: 5,977
Likes: 3,171
From: Colorado
98 F150 5.4L E40D/4R100
Joined: Nov 2006
Posts: 28,523
Likes: 7,633
From: MI
I said in post: 22415 the vehicle is a 2000 4.6 V8.
If it's not limited slip, then why is friction modifier necessary in the rear differential ?
Wow, that spider gear is busted?
Damn! What a waste of new oil and all in a broken rear diff.
If the spider gear is broken why is the vehicle still driveable ?
If that spider gear breaks off will it get caught somewhere?
In the ring gear?
Can you circle some more problems in the pics provided?
If it's not limited slip, then why is friction modifier necessary in the rear differential ?
Wow, that spider gear is busted?
Damn! What a waste of new oil and all in a broken rear diff.
If the spider gear is broken why is the vehicle still driveable ?
If that spider gear breaks off will it get caught somewhere?
In the ring gear?
Can you circle some more problems in the pics provided?
If you drove it....Yea I wouldn't re-use it in a good rear end. In that one yes, catch the oil with a disposable turkey pan.
I wouldn't worry about the spider gears....
At this point, focus your energy on finding a replacement....hows that going?