4.88 in front/4.86 in rear OK?????

[desertspeed]

I am in the process of swapping a 9" into my 2001 F150 4WD. What I have discovered is that new gears for my front diff (8.8" reverse cut) are only available in 4.88, and 9" gears are only available in 4.86.

Is this close enough to be OK, or will it cause binding issues? Does anyone have any fisthand knowledge with this?

Thanks!!

[SPONSOR]

Membership in the largest desert racing community has its advantages - Participate in Forum Discussions - Send and Receive Private Messages - Maintain Public Photo Albums - Access to Groups - User Profile in our Social Network - Increased Access to more Sub Forums - Reduced Online Advertisements Join our community today

[Pete_Rose]

Is the truck full time 4 wheel drive? If yes, then its not ok, you will build up a small (very small) amount of bind in the drive line. If no, then you are ok because the small amount of bind will translate to slipage in the dirt.

[desertspeed]

Is the truck full time 4 wheel drive? If yes, then its not ok, you will build up a small (very small) amount of bind in the drive line. If no, then you are ok because the small amount of bind will translate to slipage in the dirt.

No, it is not full time 4WD- thanks for the info.

[Pharaoh XJ]

even if its a part time I think its ok specially in the sand

[85yota]

you can have like a 1% difference and be fine.

[SimonSays]

i have a dana44 front and 9in rear.. its the same thing... 4.86 for the 9in 4.89 for the dana 44... works fine.. i run the truck in 4 high all the time and never had an issue... as long as its within 1-2% u should be good....

[desertspeed]

Awesome- thanks for all the replies.

[bajafx4]

I've run a truck with a 4.10/4.11 combo on the street (when 4WD required) and never had any issues. There's probably a larger difference in final drive ratio between front and rear just because of different tire wear rates.

[loufish]

Actually running a little front gear biased works good for off road...

4:10 frt/4:11 rear is ideal, the front end turns a little faster then the rear causing the front to want to pull out of sand & mud rather then just plowing in...The bias is small enough not wreak havic on the driveline...as long as you keep off the pavement...

[summerinmaine]

This may be a foolish question, but how do you calculate a ratio so close, but not exact?

I'm in the process of re-gearing my Jeep, and for the D44 the ring is 41 and pinion is 10, so it's a 4.10 (though some call it a 4.09 and some a 4.11). If you're dealing with ring teeth divided by pinion teeth, how do you get ratios that differ by such a slight amount? Why the difference?

Does the diameter of the ring/pinion gear come into play here?