What is the easiest, low cost method to convert/install an open differential (axle code 18, 8.8 differential, 3.08 axle ratio) into a limited slip or locking type differential? This is for a 2WD truck with a 4.6L V8. I want to increase traction for the occasional snow, heavy rain, and dirt/mud road and not for 4 wheeling.

 

Check with your local 4-wheel/off-road type speed shop. They usually perform many gear drive ratio changes and spindle changes.

I had a Limited slip upgrade converting a 308 open to a 373 LS rear end 13 years ago and it cost about $200 for parts and labor. I don't know how accurate those figures are today but the off road speed shop should be able to give a accurate quote.

 

He he, U$200. Nowadays that will buy you the oil and gaskets for the rear end.
The following is from Summit Racing.
Ford Trac-Loc limited slip differential : U$190.00 or
Auburn Locking spool: U$280
Labor to install either about U$300 to U$500.

You may want to upgrade your rearend gears at the same time. The 3.08 ratio sucks big time. Going to a 3.55 will improve acceleration and add about 1 mpg.

Ford gear set: U$200
Bearing and shim kit: U$150
Reprogramming the computer or changing the speedo gear: U$ 100 / U$25
Labor for install: U$300 to U$500 (includes the trac-loc).

Total cost for Trac-Loc only: U$500+
Total cost for Gear and LS: U$900+

Fritz

 

The fastest, easiest, and possibly the cheapest would be to find an 8.8 with a 3.73 and a LS from a junkyard. The only thing you need to be careful about is what happened to the truck before it was junked (ie hit rear, hit front, hard hit, etc). If you can find the complete axle its only a 15-30 min swap completely bolt in (provided you stay with an 8.8 and you keep your rear brakes, either drums or discs, the same).