best gear setup for 62 CJ5

Hey gang, I have 5.38 (5.375 actually) in my Dana 44 rear axle and need advice on what will be best. I have the 225 V6 with a t-90 with Warn OD, Dana 18 and plan on puting 33s with a small lift when I get further in the build. I will probly be doing mostly street and freeway driving and a little trail messing around. Since I have the OD, do I need to go as far as 3.73s or would 4.10s or 4.56s be better overall? A calculator said at 60mph the rpms would be 3300 with the current setup. any advice would help.
thanks for the help
JC

 

I have read many posts of ppl stating over and over that 4.88s with a Warn OD is the best overall setup. But you do emphasize that you will be doing alot more street driving than wheeling. Lets see what the EarlyCJ5.com hive mind has to say.

TD

 

i've got a 70.v6,od with 373's,good for allround but if you're into heavy rockcrawlin lows too high.but for general 4x4in it's good

 

Where did you get the 3300 RPM at 60? I used the Novak calculator and got 2465 at 60 mph. Your final gear ratio is 0.75 with the overdrive. A 33" tire is pretty tall for these vehicles; I think your final drive ratio is close to ideal for these tires.

http://www.novak-adapt.com/knowledge/gearing.htm

 

I would figure the RPM's as it was when it was stock at it's normal crusing speed back in the day. Then I'd try to match those RPM's wtih the tires and speed you want to go, 60 MPH.

 

My 69 CJ5 came stock with the 4.88's and they work pretty well with the stock 225 (headers/450 Holley), 31x10.5's, and the Warn OD. The 4.56's would likely also work for your application but the 4.10's might be a tad high. I am using 4.10's in my 3B with a Warn OD (33x12.5's) but I probably have twice the low end torque available from the 225.

 

Yah, I did calculate the rpm without the OD so that was the problem. Sounds like maybe i might think about running with just 31s first as see how it goes based on the collective's advice.

 

As of September 1st 1964 the now famous "Warn Overdrive" became ...Approved "JEEP" Special Equipment".
Kaiser Jeep Corporation recommended the Warn overdrive only for the 5.38 and 4.88 final drives. But that fact is a seperate issue.

I would recommend that you try out your 5.375 gear ratio.
You can change the final drive ratio nearly as easily later on if not satisfied.
I believe most will find the 4.88 final drive with 25% overdrive to be nearly ideal for onroad / offroad useage.

 

I have a 71 with a 225 and 4.88s on 31s. It's not geared low enough for good control in the rocks. What are my options? Is there a low gear set for this T-case?

I looked into a 4spd with a granny 1st since I have some SM465s sitting around but it looks like I would have front driveshaft/trans clearance issues and would have to run the small driveshaft which doesn't make sense strength-wise.

 

Looking like I have a T14 with a D18 = Crawl ratio 37. Not too good. My top speed is also about 50 mph, which doesn't really matter as I just putt around town or trailer it to the dez. Not much for gearing in these ole beasts.

"Crawl ratios in the 60's are quite capable; in the 80's, very respectable, in the 110's, impressive and anything beyond the 130's is usually considered the point of diminishing returns."

 

I had the 5:38's with the OD and an SM465 in my old 69. 1st gear was almost useless for me, but then again the 465 has a reallly low 1st gear. Otherwise the setup was ideal. Highway cruising was not a problem, since you don't want to be going over 70 in these things anyway :driving: I believe I was running an unusual size tire also (34 x 10.50):? I remember it was taller than 33's but not as tall as the 35's (SOA conversion)

 

1st wouldn't be used except for rock crawling. I want to be able to creep up one side and down the other of a bowling ball sized rock or curb without having to mess with the clutch/throttle.

I *think* I might have a 420 that needs rebuilt around. Looks like the golden setup, short of an NV4500.

http://www.novak-adapt.com/catalog/kit_422.htm

...now let's see what I have to do to mate it to the 225....

If you need to join this transmission to a GM truck bellhousing (versions from 1968-1991) with the 5-1/8" bore, it can be done. Novak offers a bellhousing locator sizing ring, part #BR4. We also sell new, billet steel SM420 bearing retainers turned to the dimension you require.

 

Nuttin' like a nice granny 1st...