[Brantly]

Just bought a 79 bronco after cruise( always wanted one), got it pretty cheap so i realy dunno the temperment of the truck. I put it in nuetral and shifted to 4H then put it in park and locked the hubs. As i rolled forward(not giving any gas) it felt like the wheels started to gradualy lock up. It sounded as if the front wheels were locking up, no gears grinding, just sounded like locking the hubs locked the axle up all together.
So i decided to put it in reverse and see, the same thing. it rolled for a while then started seizing up.
I dont think its a problem with the gears but i dont realy know. I unlocked the hubs and drove in 4H and it drove fine. well if anyone has any ideas i would appreciate it, Ive never worked on 4 wheel drive sytems before and dont know what it could be.

 

[85f150]

if i were you i would put it up on jackstands and do that testing of the four wheel. The way it sounds though is like it is a prob in the hubs, because when just the t case is in 4 hi it will turn the driveshafts, then the diff, then the axles. when the hubs lock in they connect the power from the axles to them...i can't really think of a prob in the hubs causing it took lock the tires up and actually be strong enough to do that.

 

[Brantly]

Tanks man it doesnt lock up totaly, it just starts to get really tight and sound like something is bending i dont got it in me to see what the outcome would be to give it gas and see what happens though hehe. i will get it up on stands and see what i can figure out.

 

[Lonewolf]

You said you didnt know anything about the truck,right?? It sounds like the gear ratios are different.I would check that first.
LONEWOLF

 

[drexelsteve]

You said you didnt know anything about the truck,right?? It sounds like the gear ratios are different.I would check that first.
LONEWOLF

thats what came to mind here too. ford or aftermarket hubs?

 

[Brantly]

They are WARN hubs dunno if that is stock or not( yes i really dunno much about Broncos) 8(. But i got a sweet 73 stang.

 

[Brantly]

Okies about the gear ratios, they have to match the back end?

 

[Mrit]

Yes, the gear ratio's have to match front and rear.

Are you doing this on cement/asphalt?
Do the tire size's match front and rear?

 

[Brantly]

Cement aye tires do match. It rolls fer a few feet then just tightens up. i didnt want to push it.

 

[Mrit]

Driving on the cement in 4wd is the problem. It will make the drivetrain bind up. 4wd should only be used on somewhat slippery stuff dirt/snow/mud whatever :thumbup

 

[Lonewolf]

The gear ratio is the only thing it could be. I have bought 2 4x4's in the past that had the same problem. You said you got a sweet deal,right?? Now you know why,but IT AIN'T NO STEP FOR A STEPPER!!!! Just find your axle ratios front/rear and I'm sure someone in here has the one you need. Hope this helps.
LONEWOLF

 

[85f150]

if you put the whole truck on jackstand so none of the tires are touching the ground you can start the truck up, put it in 4 wheel and observe if the tires are moving at a different speed. or you can do just jack the back up and mark the driveshaft and count how many times the driveshaft turns to make the tires go around once. and then do the same for the front. the number will be your gear ratio. ex- driveshaft turns 3.5 times to the tires once, the gears would then be 3.55 or 3.54. IIRC there can be a 10% difference between front and back before probs, it might be smaller than that though

 

[Brantly]

Hey, thankx alot guys big help i will be jackin it up this weekend to see whats up. :usa

 

[drexelsteve]

just be careful doin it :thumbup

 

[85f150]

yea it is hard to type if the tire is on top of you

 

[slim]

Driving on the cement in 4wd is the problem. It will make the drivetrain bind up. 4wd should only be used on somewhat slippery stuff dirt/snow/mud whatever :thumbup

Driving on cement is not a problem with the same gear ratios. Plz explain this one to me.

 

[84brownbronco]

yeah driving on cement in 4x4 isnt a problem as long as you arnt turning really tight. going straight is fine.

 

[Jayrus]

Might possibly be a siezed u-joint also.Try jacking up one tire and locking the hub.Then try to turn the wheel with the t-case in 2wd.If the wheel spins the hub and the u-joint are not the problem.

 

[Mrit]

Yea I must of missed the part where he said he only rolled a couple feet.

Driving on cement is not a problem with the same gear ratios. Plz explain this one to me.

It can be a problem if you turn though. I thought he was driving on the road, but my mistake.

 

[smokinjoestein]

I put it in nuetral and shifted to 4H then put it in park and locked the hubs. As i rolled forward(not giving any gas) it felt like the wheels started to gradualy lock up. It sounded as if the front wheels were locking up, no gears grinding, just sounded like locking the hubs locked the axle up all together.

Maybe its me but it sounds like you are engaging the 4wd wrong I usually lock the hubs first then get back in the truck and shift into neutral hit 4 Hi then the front drivetrain locks together. I dont know maybe that could be the problem. I know it sounds stupid but try it. I always thought you lock the hubs before you drop into 4wd (no matter whether it's 4hi or 4lo). Just a suggestion Let us know what you come up with.