I have a 88 F-150 4x4 xlt lariat. axel code H9 (limited slip differential)( 3.55)

I got new rear end from a 88 F-150 2x4 xlt lariat. axel code 19( Conventional non-positraction differential)( 3.55)

What is the difference between the two??? And which one is better for me???

 

ok here is my problem, and a solution but i need some advice PLEASE. I wreaked my axels, and my spider gears are missing teeth (3L55)
I got complete rear end from wreaking yard, only its not limited slip.(3 55)
my plan was to swap the rear ends, but I still want the limited slip.
my new plan is to take the axels, and spider gears out and put them into the rear end with the limited slip. Will this work, or are the spider gears different size??? thanks for the help

 

IIRC, the spider gears don't match up and when installing a limited slip, you have to remove the carrier assembly and then reset the gear pattern and backlash. Not exacly a job for the novice.

 

Your best bet is fine a axle that does have a T-loc in it.

As long as your swapping in a new rear end, get a 9" from a 70's F-150, its a bolt in swap, a has a stronger spider gear set.

Also a 9" very well may be cheaper to buy than another 8.8

My local yard charges $225 for a 8.8, and $100 for a 9"

the only downside is you will loose your rear abs.

 

thank you for the reply guys. Here is what i did. As per my second post listed above. switched the axels, put in new bearings, and seals, and replaced the 2 spider gears only. It turns nice and smooth so I think it will be all right, I guess i'll find out in a week when it will be running if it blows or not. I also found out why the spider gears went. The tempered steel piece that gives you the trac lok was hitting them. Not a very good design, unless mine is a defect in being to high. I would have grind it down but I installed it before I notcied It was to long. I might have to try that old 70 rear end after all LOL.

 

From the axel tag are youo able to tell if you have an 8.8 or a 9.0? Thanks

 

Daveman, the easiest way to tell the difference between the 8.8 and the 9" is to look at the axle. The 8.8 has a sheetmetal rear cover that bolts onto the housing from the rear (like a Dana axle). The 9" has a welded rear cover and has a removeable 3rd member that bolts onto the front of the housing, where the driveshaft attatches. The front of the 8.8 housing is one piece, integral with the rest of the axle housing.

 

Thanks for that info. I do have one more question about ford's "Traction Loc" rear end...I HAVE traction loc, but am unsure what exactly that means. Is it a POSI, or is it a POSI with a Lock (doubt that) and how does it function differently from a conventional rear end? Is it a good thing to have?

 

Daveman, Traction Lok and Trac Lok are Ford and Dana trade names for a limited slip differential. Positraction is a GM trade name for a limited slip, so a posi and a trac lok are the same thing: limited slip.

The way the limited slip works, is it has a set of fiber metal clutch packs that go between the 2 output ends of the differential. As long as both tires have equal traction, the clutches stay locked together. As one wheel loses traction (or when going around a corner), it exerts a slipping force on the clutch packs. The clutch packs will start slipping and allowing the wheels to turn at different speeds. The tightness of the clutch packs and the force exerted on them by the tire that's trying to slip will determine how much the slipping wheel is allowed to slip.

A tight limited slip can be great offroad, and a loose one can be only marginally better than a regular open diff. Like any clutch, they do wear out over time, but can be rebuilt for not too much money. Generally, a limited slip is a good thing to have and is more desireable than a standard open diff.

 

thanks for the explanation, you answered all of my questions, but one more before I go...What should I notice first as the diff begins to wear out and about how many miles can I expect to put on it before it will need to be replaced?

 

As the clutch packs wear out, the diff will become less effective at limiting wheelslip. Some guys are saying thiers are wearing out as early as 75K miles. How long it lasts probably depends on how you drive with it. They take a special lube in the gear oil, called friction modifier, that keeps the packs working smoothly. I imagine keeping them lubed would make them last longer. Mine are still working satisfactorily in the Bronco with 130K+ miles, but I don't know if they are original, kinda doubt it.

 

Would temperature extremes accelerate the wear? I am located in Ontario, Canada and our temps range from about 110 F in the summer to about -40 F in the winter.

 

I don't know. I imagine the cold would make them want to stick more/slip less, but that's just a guess.

 

For those of you who are in the know, anyone have a rough idea how much it would cost to go aftermarket and add a decent limited slip differential to an almost brand new 04 F-150, I've got the 3.55. I know, I know I should have ordered it but I didn't, now I'm reconsidering...