okay so i have kinda read up on it, and apparently its bad. My question is why? why would a different differential ratio be bad. I don't have much understanding of them in 4x4 apps. My newb/uneducated way of thinking about it, leads me to think, that you would merely be delivering power at different rates. Would this mess up the TC? is that the reason

sorry for the dumb question, but the reason I am asking is because I am planning on doing lockers, but prob can't afford to do them at the same time. I will eventually need to change ratios to like a 4.30 or 4.56. it would be nice to be able to do the ratio change at the same time as the diff locks(ARBs fwiw)

 

yeah, big time noob ? here, but if you change the ratio in one differential and not the other, then whenever you go into 4wheel-drive, then one set of tires would be trying to spin at a different speed than the other, which would really only be possible to do in some kind of crazy slick mud. bottom line is: if you regear in one diff, then it has to be done in the other if you plan on using the 4hwell-drive...

 

you want the front and rear tires to spin at the same rpm. not doing so will cause components in the driveline to break.

 

The only way you can do this is on vehicles with a selectable center differential, otherwise, you'll always be spinning some tires when you're driving (if you're lucky). If you're unlucky, something in your transfer case or elsewhere in the driveline will break.

Bottom line, unless you have a selectable center differential, both the front and rear driveshaft need to rotate at the same speed. This is impossible (without spinning tires) with a different gear ratio front and rear, unless you also have different tire sizes front and rear perfectly sized to offset the different gear ratio, and it could be tough to find the right tire size combination to do this.

 

Of course I know its wrong but, I'd love to see the carnage if someone tried this.

 

Why is it bad? Its been discussed at length. You cannot deliever power at different rates because all 4 wheels are on the ground and must spin at the same rate. Is it bad for the transfer case? Yes. It could also be bad for the diffs.

You will either blow up your tcase, or those fancy new ARB's you plan on getting.

Here are your choices: Buy one set of gears, a locker and try to use 4wd, have to replace one or more of the following: front diff, rear diff, axles, drivelines, transfercase etc...Then buy the second set of gears anyway.

Just buy both sets of gears. No fixing of anything...

It cannot be done. If you try it, you will have a very expensive fix.

 

i was just wondering... thanks for the info guys. i knew it was bad, like i said, i read some of the posts about the subject. I just wanted an explanation. all the posts were somewhat helpful, but GSGallant's gave me the info I didn't have.

I have spent all my formative car years building higher HP cars(~400-500WHP. Nothing to worry about on the front wheels, cept bigger brakes maybe, haha.) Thanks again for the info guys.

 

Serious mud boggers will run the front wheels faster to get them up on the surface but thats a specific case. I think the older (really older) broncos ran 4.11 with 4.10, but thats miniscule if used off road. Put different tires front and rear sometime, in 4x4 you will bind everything up solid in about 10 ft and have to back up to get out of it. The horrendous bang if you try and unlock the TC is something too!!! Dont do it.