Getting your borg warner 1356 transfer case rebuild kit ordered is usually the first real sign that you're committed to fixing that old Ford sitting in the driveway. If you're driving an F-150, F-250, or a classic Bronco from the late 80s to the mid-90s, there's a very good chance you've got a BW1356 tucked under there. These things were the workhorses of the era, handling everything from grocery runs to heavy-duty hauling and mud-bogging. But let's be honest—nothing lasts forever. After a few hundred thousand miles, the bearings start to howl, the seals start to weep, and you realize it's time to crack that magnesium case open and give it some love.
Choosing the right kit isn't just about grabbing the cheapest box of parts you find on the internet. It's about knowing what your specific unit needs. These transfer cases came in both manual and electric shift versions, and while they share a lot of DNA, you don't want to be halfway through a Sunday afternoon teardown only to realize you're missing a specific seal or a small snap ring that wasn't included in a generic pack.
Why You're Probably Looking for a Kit Right Now
Usually, the 1356 doesn't just die quietly. It'll give you some warnings. Maybe you've noticed a puddle of ATF on the garage floor, or perhaps there's a rhythmic "thunk" when you let off the gas. One of the most notorious issues with these units is the internal oil pump. Over time, the arm that holds the pump in place can actually wear a hole right through the case. It's a design quirk that has sent many a truck to the scrap yard, but if you catch it early enough with a solid borg warner 1356 transfer case rebuild kit, you can save the whole assembly before it grinds itself into metal shavings.
Another common reason for a rebuild is simple bearing wear. If your transfer case sounds like a box of rocks when you're cruising at highway speeds, those needle bearings or the main output shaft bearings are likely toast. A rebuild kit refreshes these high-friction points, restoring that smooth, quiet operation you probably haven't experienced since the Clinton administration. It's a satisfying project, but you've got to be prepared for what's inside.
What's Actually Inside a Good Rebuild Kit?
When you finally get that box in the mail, you should see a pretty specific collection of parts. A standard borg warner 1356 transfer case rebuild kit generally includes all the essential bearings—main shaft, input, and output—along with a complete set of seals and gaskets. You'll also usually find the small stuff that people often forget, like the O-rings for the shift rail and the caged needle bearings.
Don't overlook the quality of the seals. The 1356 uses a magnesium case, which is great for weight but can be a bit finicky with heat and corrosion. You want seals that are going to hold up to the elements. Some kits also include the plastic shift fork pads. These are tiny, inexpensive pieces of plastic, but they are absolutely critical. If those pads wear down to the metal, your shift forks will start grinding against the synchronization hub, and then you're looking at much more expensive repairs than just a basic rebuild.
The Oil Pump Issue You Can't Ignore
I mentioned the oil pump earlier, and it's worth diving deeper into. If you're doing a rebuild, you must inspect the pump. Most basic kits don't actually include a brand-new pump—they usually just give you the seals for it. However, because the BW1356 pump has a tendency to "walk" and eat into the case, many people choose to upgrade the pump stay or "bracket" while they have everything apart.
If you open your case and see that the pump has already started carving a notch into the magnesium housing, don't panic. There are aftermarket "pump fix" kits that work alongside your borg warner 1356 transfer case rebuild kit to reinforce that area. It's one of those "while you're in there" jobs that saves you a massive headache five years down the road. It's honestly better to spend an extra thirty bucks now than to have to hunt down a new case half later because your pump decided to exit through the side of the unit.
Manual vs. Electric Shift Variations
One thing that trips a lot of people up is the difference between the manual-shift and electric-shift 1356 units. The internal guts are remarkably similar, but there are differences in the shift cam and the way the speedometer drive works depending on the year and the specific truck model.
When you're shopping for your borg warner 1356 transfer case rebuild kit, make sure you've checked your tag. There should be a metal tag bolted to the rear of the case with a long string of numbers. That tag is your best friend. It tells you exactly which variation you have. Some older versions use a mechanical speedometer cable, while later ones moved to a vehicle speed sensor (VSS). If you buy a kit designed for a '96 and you're working on an '88, you might find yourself staring at a seal that doesn't fit.
Don't Forget the Drive Chain
Here's a little secret: most rebuild kits don't come with the drive chain. I know, it's a bit of a bummer. But the chain is a wear item just like the bearings. Over time, the chain stretches. If you've ever been in 4WD and heard a loud popping sound under heavy load, that's your chain jumping teeth on the sprockets.
Since you're already going through the trouble of pulling the transfer case, draining the fluid, and splitting the cases, you really should check the chain tension. If there's more than about an inch of slack, just replace it. You can usually find the chain sold separately or as part of a "master" borg warner 1356 transfer case rebuild kit. It adds to the cost, sure, but putting a stretched chain back into a freshly rebuilt case is like putting old, dirty oil back into a brand-new engine. It just doesn't make sense.
A Few Tips for the Actual Rebuild
Working on a BW1356 isn't rocket science, but it does require some patience. Since the case is magnesium, you have to be careful with the bolts. Magnesium is soft. If you go at it with a giant impact wrench and no finesse, you're going to strip those threads out faster than you can say "helicoil." Use a torque wrench when putting it back together, and stick to the factory specs.
Also, keep your workspace clean. Transfer cases are full of tiny passages and needle bearings that hate dirt. Lay everything out in the order you took it out. I'm a big fan of using egg cartons or labeled plastic bags for the small clips and springs. There's a specific thrust washer in the 1356 that likes to hide in the old fluid at the bottom of the case—make sure you don't accidentally toss it out with the waste oil.
Lastly, let's talk about fluid. These units typically take Mercon ATF. Don't try to get fancy with heavy gear oil unless you want to burn out the pump and ruin your new bearings. The tolerances are tight, and that pump needs the thinner viscosity of automatic transmission fluid to move through the internal galleries and keep everything lubricated.
Wrapping It Up
Rebuilding your own transfer case is a bit of a rite of passage for truck owners. It's one of those jobs that seems intimidating until you actually get the borg warner 1356 transfer case rebuild kit laid out on your workbench. Once you see how logically these things are put together, it all starts to click. You're essentially taking a piece of 30-year-old machinery and giving it a second lease on life.
Whether you're fixing a leak, silencing a noisy bearing, or preventing that dreaded pump rub, a solid rebuild kit is the foundation of the job. Just take your time, keep things clean, and don't forget to check that chain. Your truck will thank you the next time you shift into 4-High and everything works exactly the way it's supposed to. Happy wrenching!