Welding the front diff is a bad idea. The difference in the wheels' rotational speed is much greater in the front end vs the rear when turning. Factor in a series of articulating joints on the front where the rear has none and you've got a recipe for mechanical failure. Rear axles can get away with "Lincoln Lockers" (welding) or spools to some degree because the difference in wheel speed isn't as great and all the output goes to a single set of shafts. And from what I've heard from those who have tried, steering with a welded front end is nothing less than squirrely, to say the least. I'd say try looking for a used Mazda Miata LSD (geared/Torsen or clutch) for the front. They are a drop-in fit for the 7" front end of the Kia. I would go with the Torsen because they are strong and won't blow the clutches if you slam a wheel down after getting it in the air... And they don't need special gear oil, either.

A welded front would be virtually impossible to turn; especially at speed. You can get away with it in the rear; HOWEVER, tire wear is accelerated and as mentioned, excessive pressures are put on suspension.

But, for full off-road use, works great....

BTDT with a welded rear diff...

John Stewart
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