Differential Rebuilding

Text Box: Serving the San Francisco Bay Area since 1988 
Text Box:   Rearend
Text Box: What We Do

Rebuilding differentials is the heart of our company, we’ve rebuilt over thirty thousand of them in the twenty years we’ve been in business. 


From 1929 Studebaker Commanders to 2008 Honda S2000’s, we can get your vehicle back on the road fast and with the job done right the first time.

We carry a full line of parts for most RWD/4WD cars, light trucks and SUV’s, and our technicians can install them in your vehicle faster than it takes most shops just to figure out what’s wrong with your diff.


Whether you just have a noisy wheel bearing or the entire contents of your differential is laying in a puddle of oil in your driveway, we’ll have you back on the road in no time at a price that’s lower than factory dealerships and most independent service outlets. Specialized service does not mean extra-high prices or long waits!


For example, you have a 1999 Dodge Durango 4WD that’s making some growling noises from the rear differential. Our price to rebuild the limited-slip unit with a new clutch pack and install all new Timken internal bearings with new seals  would run about $605, parts and labor, and the job can be done in a day.


Say you have a 2002 Ford Econoline 150 delivery van that’s making terrible noises, clunking, banging, thumping—it barely moves. Get it down to us and we can install new ring-and-pinion gears, new spider gears and all new bearings & seals for roughly $875, parts and labor. Make a special appointment and you can even wait for it—no downtime for your business vehicle!


Or, maybe you have real trouble. You’re the proud owner of a 2003 GMC Sierra 1500 that has a giant gash in the differential cover and parts falling out of it. It’s going to need EVERYTHING—new axle shafts, new limited slip unit, new gears, new cover—it’s a mess. To install ALL new parts in your differential housing will cost you about $1460, parts and labor, and can still be done in a day or two. Yeah, it’s a lot of money, but check out what the dealership wants for the same job. Then see what a wrecking yard wants for a used, untested unit with a short warranty. You’ll probably be giving us a call.

Gear changes

     One of the most popular performance enhancements you can do to your automobile or light truck is to change the rearend ratio.


     Whether you’ve modified the engine to produce more top-end power, installed a larger tire/wheel combination, or constantly tow heavy loads, a gear change can help your vehicle perform to it’s full potential.


We stock a full line of performance gearsets for most applications, or, if you prefer, you can bring in your own gears and we’ll install them in your vehicle or differential. Ether way, you’ll get the most precise installation possible so your gears can live a long, trouble-free life.


To give you an example, say you drive a 2006 Ford Mustang GT and want to lower the gear ratio to 3.73 for better off-the-line performance. For us to supply new Ford Motorsports ring-and-pinion gears and install them in your vehicle, it would cost you about $640, parts and labor.


Perhaps you have a Honda S2000 and have purchased an aftermarket gearset, but aren’t comfortable trying to do the job yourself. The labor charge would run you about $450 if you drove the vehicle into us or $200 if you pulled the differential out and brought it to us.


Or you have a 2004 Chevrolet Silverado 4WD pickup truck with 35” tall tires and the stock 3:73 gear ratio, and your performance just isn’t what it should be. To switch the front and rear differentials to 4:56 ratio OEM gears would cost you about $1300, parts and labor.

26’s, anyone?

Limited slip and locking differential installation

Traction. You don’t think about it until you don’t have any, and then you need it more than words can express.  We understand. At Rearend Specialties, we’re experts at helping you get the power to the ground, whether it’s at a dragstrip, in the mud, at a boat ramp or at the ski resort.


We stock a full line of limited-slip units, including Auburn™ , Eaton™ , Detroit Locker™ , Dana/Spicer™ , TrueTrac™  and OEM units, and can install them into your vehicle or differential in a jiffy. We’ll also install your Air-Locker™ , OX Locker™  or Auburn ECTD™  electronic locking differential, no problem. We even carry spools for the most popular drag race applications and can special-order anything else you need.

For example, you’ve got a 1993 Chevrolet Silverado 1500 and you just can’t pull your boat out of the water when the ramp’s mossy. We can supply and install a new Auburn limited-slip unit for around $625, parts and labor and it only takes a few hours.


Or maybe you’d like to take your 1998 Jeep TJ Wrangler offroad, but it just slips and slides when the going gets rough. We can put a Detroit Locker  in your Jeep for about $875, and traction will be the least of your worries.


Perhaps you’ve bought an Air Locker for your 1985 Toyota Land Cruiser and you’ve hooked up all the air fittings, but would like someone else to install the ARB into your pumpkin. No problem, we charge about $375 to install it into your vehicle or $175 to set it up in your differential if you carry the unit in out of the vehicle.

Serious tires

Narrowing, straightening and welding

    The hardcore stuff. Procedures that require gloves, goggles and glasses, plus a willingness to endure a little fire, smoke and burning hair. No problem, we’re used to it.


   Differential too wide for those big ‘ol tires? Narrow it, don’t downgrade to skinny meats. Rearend Specialties uses Alston and Mark Williams housing jigs for pinpoint accuracy, and we carry Strange and Moser Engineering housing ends. Narrowing charges run from $175 if the housing is carried in clean and bare up to $350 if we need to disassemble/reassemble the gears, bearings and brakes (axle replacement/resplining not included). We’re a Moser Engineering distributor if you need new axle shafts, or we can send out your old ones for resplining if need be—call or come by for prices.


    We can straighten many differential housings that are damaged due to improper welding or collision damage, but we have to see how bad the damage is before we’re absolutely sure we can fix it, as severe  bends require a new housing for safety’s sake. Axle housing straightening can range between $100 if the housing is clean, stripped and bare to $250 and up if we have to completely disassemble the brakes and gears and hot-tank the housing, assuming the differential is already removed from the vehicle.


   You need brackets welded on? We got you covered. We stock new OEM-style GM spring perches in both multi and mono-leaf configurations, extra-narrow perches for old Jeeps and other antiques, plus the standard 2—1/2” pads for most other leaf-spring cars and trucks. Typically, it runs about $100 labor to cut off your old spring perches and weld on new ones, plus the cost of the perches.


If you have other types of  brackets to weld on—four-link mounts, back braces, shock mounts, etcetera, we’ll be happy to quote you a price after seeing the extent of the job.

Things we don’t do

Sorry to be the bearer of bad news, but here’s a list of work that we don’t perform here at RS.


We don’t build driveshafts or leaf springs, we don’t do suspension work or wheel-tubbing, and we don’t work on FWD transaxles or transfer-cases, although we can usually recommend someone who does,.


Rearend Specialties doesn’t work on medium or heavy-duty trucks over 1-ton capacity.


We don’t do total disc-brake conversions on vehicles or narrow rearends in-the-car, you’ll need to pull the differential out and bring it to us in order for us to shorten the housing.


And there are a few differentials such as Jaguars, Subaru AWD rear diffs and some Mercedes units that must be brought in as bench units, out of the car—call us for more info if you’re concerned this applies to your vehicle.


Other than that short list, we’ll pretty much handle whatever  differential-related job you can throw at us, give us a call or come by!

Tall tires, low car.