F150online Forums - 4WD with different front and rear gear ratios

F150online Forums (https://www.f150online.com/forums/)

- Other Powertrain (https://www.f150online.com/forums/other-powertrain-15/)

- - 4WD with different front and rear gear ratios (https://www.f150online.com/forums/other-powertrain/351809-4wd-different-front-rear-gear-ratios.html)

Quote:

Originally Posted by Hash278 (Post 3446572)

Probably never thought he would use his 4wd since he's running 24's......:devil:

Should've been prepared for it anyway

No i shoud've just bought two single cab f150's instead of a super crew.

Quote:

Originally Posted by blackf150337 (Post 3446744)

No i shoud've just bought two single cab f150's instead of a super crew.

That might have been better so you could run different ratios in one and the same in the other...:thumbsup:

Quote:

Originally Posted by Hash278 (Post 3446752)

That might have been better so you could run different ratios in one and the same in the other...:thumbsup:

lmao

Quote:

so i engaged my truck into 4 high and started to give it gas and nothing...so i put it into 4 low and i started to pull myself out, scared of breaking something in my transfer case (due to non matching gear ratios) i went into neutral and then to 4 high...and gave it gas and i got a tick tick tick tick noise from the front no front wheel motion at all...so i put it in 2wd and let my buddy pull me out....The question is what the hell happened?? My truck drives perfectly in 2wd did i break something in my transfer case or front diff?

....Yes.... :rocker:

Could be either one really... When it binded up on you, the weakest part out of all the parts needed to make it work is what gave more then likely...

What that part is, it's anybodies guess???

You might be able to trouble shoot some by disconnection both front and rear drive shafts, put it in 4wd and see what output shafts still spin, or if there is a rock and gravel sound coming from the TC.... Once you have the front drive shaft off, try to spin the front diff and see/hear/feel what happens there....

It's too late now, but what other folks have done when they have different gear ratios on front or the rear is remove the front drive shaft, so that there is no way of engaging until both are the same... You just have to put up with being a 2wd rig until then... But, hindsight is 20/20, so there you go! Lesson learned....:smoke:

Good luck and consider it an expensive lesson in mechanical engineering...

Mitch:beers:

wow..... just wow....

:lurk:

Someone needs to post this over on pirate. The guys over there know there chit and can help you out right away.... :devil:

so DID YOU figure out what happened yet?

Quote:

Originally Posted by blackf150337 (Post 3446742)

i doubt i broke the transfer case, i've heard of people doing that all the time in the dunes...i had absolutely no traction on the back tires so how would that have been such a problem...even when i got pulled out the hole the rear tires were just spinning on dry dirt b/c there was no traction?

Yes, only because they are also running different size tires. IE- 3.73 in rear with 35's and 4.11 in front with 33's.. (did not calculate btw- just an example)

Jon

Quote:

Originally Posted by GJ Screw (Post 3448108)

Yes, only because they are also running different size tires. IE- 3.73 in rear with 35's and 4.11 in front with 33's.. (did not calculate btw- just an example)

Jon

Yup, I have seen that, so that in the end, the ratio is the same, or close enough.

If you have close gears (3.50 and 3.55 or something) your good. To far..... bad.

as they shouldnt. try it in 4x4 with the truck running

Quote:

Originally Posted by blackf150337 (Post 3448346)

i dont think it happened b/c of the different gear ratios like i said the rear tires had absolutely no traction at all, even when i got on dry dirt it took a good couple of revs to get all that sticky **** off my tires to get some traction.... i think it was b/c i was running in 4lo with 3.73 up front and 37's too much torque and too much traction up front something had to give...i think there's something wrong with the front hubs...the cv shafts do not turn when i drive and my front drive shaft can turn if i rotate it with my hand.

i dont think you understand. it doesnt matter if you dont have traction or not. If you put it 4wd and touch the gas the gears in the T-case will want to turn. Even if you were in stuff that was so sticky that the tires wouldnt turn. But seeing how you said you had "no traction" that means the rear tires would spin then when you attempted to engage the 4wd you messed up.

The only hope you have is that something was wrong with the 4x4 system previous to you trying to engage it with unequal gears. If this is the case then the t-case may not have engaged which would mean no damage could be done.

:lurk:
I can't wait to see how much this is going to cost to repair

27-21

Quote:

Originally Posted by blackf150337 (Post 3448573)

so if my truck was on a lift...with all four tires off the ground and i engaged the 4wd i would have put the 4wd in a bind?

No, the fronts and rears will turn at different speeds. This is the ONLY safe way to engage 4wd with different ratios - when all 4 wheels are off the ground.

Quote:

Originally Posted by glc (Post 3449182)

No, the fronts and rears will turn at different speeds. This is the ONLY safe way to engage 4wd with different ratios - when all 4 wheels are off the ground.

exactly!!

But you werent off the ground you were still under load. Just cause your tires didnt have enough bite to move you doesnt meen there was zero traction. Theres always traction, just sometimes not enough.