just wondering i looked at a bronco with a 6 inch lift kit for sale but the front gears are blown the guy tells me.so it has 2 wheel drive but no 4 wheel drive right now.it has 4:46 gears in it cause it has 35s on it.they guy told me he only drove the bronco on the street 94 bronco with a 302.how the heck would the front gears blow out like that just driving down the street?maybe hes making that up who knows.

 

A Bronco, or anything for that matter with broken gears are that way from use and abuse.
Gears cant just break without something going wrong. That front end would have to be engaged and beaten down in order for the front ring and pinion or other gears to be broken.

 

Yup, the only thing other than a bad setup or no gear oil would be stress from ragging on it.

 

This is similar

I see tons of bronco on Craiglist in Michigan they say bad rear axles. how they kill rear axles but no hitch on it. They say it just sudden grind then lock.

Did that front axle have posi or locker? Sound like he weld diff to make locker then he try turn and it end broken gears teeths. Or installer did bad job on it.

 

Another thing to consider is that 98% of the time when someone diagnoses what's wrong with a vehicle they're selling, they're completely wrong. Either out of ignorance or deceit.

 

yeah I was thinking that to that he doesn't really know what it is and he's guessing .I was thinking it may be the hubs since there the electronic crap type.just trying to figure a way to tell what it is since he wont let me take it apart.

 

Would he let you take an oil sample out of the fill plug? If it really grenaded then you might get some bits and pieces of trash out.

 

Automatic locking hubs make troubleshooting a problem. Although you can spin the driveshaft by hand to determine where aproblem can be found. Since the TTB axle has exposed shafts, you can see the individual shafts turn. Use a large screwdriver to lock up one side or the other, by inserting it through the stucb shaft in the open part of the knuckle. This will lock up one side and permit you to turn the opposite axle shaft. Turn the driveshaft with enough rotations to turn the rin gear at least a full rotation or two (over 4 turns of the driveshaft). This will rotate the spider gears as well as the ring gear and carrier enough to determine where something is broken.
Repeat the process by inserting the long screwdriver in the other side and watch or feel for anything obvioussly wrong.
If the ring gear is busted, or the pinion is broken, even if there is a problem with the spider gears. the axles will not move in a fluid motion and you will feel resistance in the driveshaft. If the axles turn well, and function fine then you might find a problem after the differential, but if the axles have some difficulty turning, it may be something out at the hub.
These lockouts break often, but the entire TTB front axle is a weak link when larger tires and extra leverage of gears is applied.