transfer case

I have 2 questions. I have a stock 62 CJ-5. I want a little lower gearing in low range, will the later model 66 to late 70s transfer case bolt in to my jeep?, I understand they are slower in low and also their is a kit to make them even slower. I have the T90 3 speed. Also I now have stock rims with 6.50x16 tires, I think I want to switch to 30x950x15 I was told this is as big as I can go without lifting the jeep. I was told that I need an 8 inch rim for this tire. My question is what would be the ideal backset for the 15 inch rims I need to have made? My stock 16 inch rims have a 4 inch backset.

 

Regarding the transfer case, the early and later model 18 transfer cases have the identical low range gearing, 2.46-1. Tera Mfg. makes a 3.15-1 low range gear set for your application and Jack O'brien makes several ratio kits for the 18. Nickmil.

 

d18 transfer case low gears are available but lots of $. I looked into this before switching to the sm420 tranny. You might want to consider changing the diff gearing instead - or the trans.

I ran 32" tires on my rig without lift springs but I did use 1" longer shackles (1/2" lift).

I think you could get by with less than an 8" wide rim with that tire size (9.50"). I've got 12.50" wide with 7" wide rims but that may be pushing it.

Backspacing. 4" would probably be fine with the narrow tire you're looking at. A little less backspacing will give more room to turn the wheels without the tires hitting the springs or frame. I need some rims with much less but haven't found any yet & will probably have to have them made.

 

I'm running 32s on a stock suspension.

 

I have 30-9.5-15's on 7" rims and they are about perfect.

JB

 

Thanks for the answers guys! I was wondering about the transfer case, because, Tera mfg. told me that I needed the transfer case from a 66 or later jeep they said it was still an 18 but had a larger case. So my concern would be,would it bolt up to my tranny, and would my driveshafts bolt up without problems.

 

I should have said, Tera mfg. said I need the later transfer case to use their gear set.

 

Yes it will bolt up and the dshafts "should" be the same.

 

I know this has been asked before but I figured someone could answer it quick. Do the D18 low ratio gears swap into the D20 fairly easily? How many gears would you have to change? Just the low range gear (1 gear)?

Josh

 

You will need a gear from a EB tcase. If you search I know the gear number has been posted before and a supplier also.

 

Thanks Jason, that helps. Thank you other fellows as well for the wheel and t-case info. I did want to use stock looking rims, I dont care for the spoked wagon wheels or mags. I suppose a simple solution to the gearing would be the use of a T-98. But I understand that moves the T-case back a few inches, and to me the shifters would look out of place, also driveshaft issues.

 

Yes and No. You will need an adapter ring to retain the mainshaft bearing on the T-90. The small hole t-case is actually the retainer in this case. Novak makes this adapter - not listed on their website but they do make it.