Hey I was just wondering what size gears I should run? I have a 89 Bronco 2 with a 2.9 and a five speed. I dont know what size gears are in there now but its a little sluggish for me. Especially on the high way downshifting to 4th every time there is a hill. I run p235/75r/15 tires, so slightly larger than stock. I dont mind about gas milage to much as long as its better than my fullsize lol. Any help would be great! Thanks, oh yeah how much would a gear swap cost roughly? Thanks!

 

i would think the stock gears should be good enough in there for them size tires. I run 4:10 gears in mine but i have 35x12.50x15 BFG AT/s on mine.

 

What kind of rpm are you getting on the highway at cruising speeds ?

 

Do you know what gear ratio you have? Stock, you could have 3.55, 3.73, or 4.1 (others?). Check the tag on the differential and/or the sticker on the door jam.
FWIW, I'm running stock 3.73 gears and 235/75R15 tires, and it seems to do fine.

 

Yeah on the door, it says the axel #42, i couldnt find the tag on the axle itself.

 

That's a 3.45 gear ratio. This assumes that the existing axle is the same as originally installed in the truck. Moving up to 3.73 or 4.10 would probably help.

 

how much do gear swaps usually cost and is it woth it on stock axles

 

hey thanks a lot guys. I knew it was a little high for my liking. Yeah do any of you guys know how much that sort of thing would cost? Thanks again

 

I'm interested in putting in the 4.10's. How much do these usually run in cost? Thanks.

 

www.partsamerica.com lists R&P's at ~$220 for the rear and ~$250 for the front. Add an additional ~$200 each axle for installation/setup (unless you really research how to do it or have experience with it, setting up gears isn't something you want to try. Tolerances are tight, and getting it wrong will eat up your new R&P within a few thousand miles). Unless you are converting to 4X2 at the same time, you really need to do both front and rear axles.
Is it worth it? If you want a stock gear ratio, it might be better to find used axles with the desired gear ratio in the junkyard. This way you could also consider getting a Ford 8.8 rear/Dana 35 front to replace your 7.5/D28 setup. If you want a non-factory ratio (4.56 or lower), you're probably better off just ponying up the dough.
And even at that, some might say that the cost is just too high and they'll keep their existing gear ratio.