axle swap gear ratio question

This is a hypothetical since I don't have the money to do it, but I wanna get my wish list straight. I have a '94 XJ 4.0L SE 5 speed Select-trac.

I have the Chrysler axle with 3.07 gears. I want a Ford 8.8 to get disc brakes and add a leaf while I am at it. I am fixing a broken e-brake cable now and realized if I do this, I will need to install the ford cable since it is axle specific.

I mainly want to do this in case I ever tow I want better brakes - I live in VT and we have serious hills so all the braking power you can get helps.

Ford makes an 8.8 with 3.08 gears if I can find one.

My question is: does the 0.01 gear ratio make a difference for the transfer case? Or would I need to do new gears, and if so how expensive are gears normally? My mechanic said it does make a difference and we would have to do gears but I am better at math than he is so I really wonder. He doesn't think different tread depths on matching tires strains the T-case at all so it is a mixed judgement.

Would I have to do gears? yay or nay?

Those ratio's will be just fine

The 0.01 won't matter. 0.01/3.07 is only a 0.3% difference. Your tires are farther out than that on the diameter. You can probably go 0.05 or maybe more different on gears without issue.

Testify - I have 3.54 up front and 3.50 in the rear - 0.01 will be no issue.

I read somewhere that you can get away with up to 3% difference or so.

If you are doing significant towing on hills, you might consider regearing anyway. 3.07 is really high for that kind of work, even on stock size tires.

8.8 sounds like a decent swap. Unless you get one already setup, you will have to remove existing brackets and weld new ones on. However, I would say find axle out of an auto XJ, stock gearing for those is 3.55. Either piece together or buy a rear disc kit. And, voila!