Enough beef for 401?

solomon

I'm a drivetrain novice. I bought a cj5 with a 401. There's no gears in the front differential. I think the guy punched it and broke some teeth off a ring gear or something. It's got a Dana 44 rear. Not sure what the ratio is yet. I've got a Dana 30/AMC 20 combo from my other CJ. My question is what would be a solid front rear combo to handle the 401. I'm not heavy footed, but I also don't want to be off in the woods and bust a gear. Price is an issue, but I'm not scared to spend either. Trying to make a list of things I want. Not sure what models the tranny/transfer case are but it's a 3 speed and the TC is 4H-2H-N-4L

MoPedal

What size tires you gonna run? Moderate or extreme riding? I would dump the 3 speed and probably go with a T-18 4 speed (or something equal) especially if you are mainly doing woods and not road. D-44's are OK for moderate.... but not extreme. D-60, 14 bolt, D-70, for extreme. Rockwell's handles very extreme trails and are still fairly cheap too but are going up in price. Mogs are great but on the expensive side. A CJ5 is a lot of fun....and exciting to wheel in! Good luck to ya!

Mudrat

MoPedal wrote
What size tires you gonna run?
Moderate or extreme riding?
I would dump the 3 speed and probably go with a T-18 4 speed (or something equal) especially if you are mainly doing woods and not road.
D-44's are OK for moderate.... but not extreme. D-60, 14 bolt, D-70, for extreme. Rockwell's handles very extreme trails and are still fairly cheap too but are going up in price. Mogs are great but on the expensive side.
A CJ5 is a lot of fun....and exciting to wheel in! Good luck to ya!

Good questions ... the size of the tire will control engine RPM. You wanna stay in the power band when you are doing whatever kind of wheeling your going to do. Example - on road your engine will need to be runing in an economical range at 60-70MPH - off road, low-range shoud be in the same RPM range, the problem is that may put you too fast for the tire size (31's vs 44's :idea: ) so let us know what it is you want to do and we can be of some more help. :?

And I want to see a 5 on MOGS!!!!! THAT would be something :wink: Been thinking about them for the 7 #-o

'Rat

tufcj

I ran a Dana44 rear, Dana30 front with 35s. I broke the front carrier once, and broke a handfull of front axles. I twisted the axle splines on the 44, but never broke a shaft. This is doing some fairly difficult rock crawling with a power-lock in the front and a Detroit in the rear. I'm currently running 44s in both ends with detroit lockers and 37s. I have a 60 fo the rear to be built some day. Gear ratios 4.10-4.56 with 33s, 4.56-4.88 with 35s and up. Keep the 44 rear and you might even go 5.13 if you're above 35s. I currently have 4.27s with my 37s, and it's not quite enough gear (street or trail). I have 4.88s waiting to go in (with the 60). Bob tufcj

MoPedal

mudrat wrote
And I want to see a 5 on MOGS!!!!! THAT would be something :wink: Been thinking about them for the 7 #-o

'Rat

Mogs on a 5 would be a sight. :lo1l: Wow what clearance!

MoPedal

tufcj wrote
I ran a Dana44 rear, Dana30 front with 35s. I broke the front carrier once, and broke a handfull of front axles. Was it the axles that broke or the u-joints coming apart? Most of the breakage on my front 44's was u-joints 🙁:

I twisted the axle splines on the 44, but never broke a shaft.
The rear shafts will twist up to 25* or maybe more....I have always been amaised how far they will twist without breaking! But I wasn't as lucky as you...I've broke a few!!

I'm currently running 44s in both ends with detroit lockers and 37s. I have a 60 fo the rear to be built some day.
How do they like those 37's??...seems like once you get over 33's they start "crackin" (depending on the trails)

I currently have 4.27s with my 37s, and it's not quite enough gear (street or trail). I have 4.88s waiting to go in (with the 60).
I think you'll really like the 4.88's and the pinion still has some meat left on it too!

tufcj

solomon

I can almost guarantee you I'll never run anything bigger than 36's, and most probably I'll stick with 33's. Those unimog axles look stout, but i read somewhere a pair weighs like 1200 pounds. I don't want anything that heavy. I won't be doing any rock climbing. Just backwoods swamp riding and some in the river sand. From time to time the mudholes get deep in the swamp and I don't want to gouge it and break something in a hole. Not looking for bulletproof, I just want to be able to hit the gas without stuff flying apart.

Dusty

4.88's with 35's in direct with a .512/.525 lift 228/234 dur @.050 112 lobe sep cam from crower on a 9.8:1 401 .030 with a T-18 in a CJ7 the combo works great little lobety lope :!: but not enough to cause any issues Performer intake is a little small but keeps up port velocity on the bottom end. Probably going to a Airgap when i get time. 770 for the carb. the 4.88's are ideal for up to 70 mph knocking on a little high on the rpm range but thats at 70 mph everything else is on the dot for good to go. I ran a scout 44 rear for a long time no issues with q powerlok front and rear now i have a 60 with p-lok and 4.88's. the 44 twisted some but never broke in 5 years oif wheeling

eight

Sounds like you need a pair of scout or wagoneer axles. Use 15x8 wheels with 5.25" of backspacing if you don't want the tires to stick out very far. They'll stand up pretty good if you're reasonable on the throttle offroad. I run 4.10 gears with 38s and would never want lower. That gives it a good cruise rpm at 60mph. Unbalanced worn swampers shake too much above 60. And I only have a 360. For offroad slow going, I have a np435 and a dana 300 which is about 3 times slower than your 3 speed and dana 20. A t-18 is almost as low and fits better. Put one of those in, and swap in a dana 300 transfer case while you're at it. The dana 300 has lower gears than your dana 20 and 4:1 kits are affordable if you want lower.

1980_Cj7

Good luck. These 401's make a LOT of torque! Here's what ours did to a full float Dana 60 rear axle the day after we got the 401 in.

mika01

1980_Cj7 wrote
Good luck. These 401's make a LOT of torque! Here's what ours did to a full float Dana 60 rear axle the day after we got the 401 in. [/img]

Alright now you have to back this up with a story!!! How the heck did this happen?

Dusty

thats only a 30 spline stock shaft from a 60 comon man more details.

1980_Cj7

True, just a stock Ford 30 spline, not alloy or anything, but full float which means it isn't taking any weight, just turning the wheel. It was done doing burnouts. The axle has a Detroit in it too. Sticky 38.5x14.5x16.5 TSL's. Aftermarket alloy shafts are the next mod.

tufcj

The 60 sitting in my garage is a 35 spline semi floater. 1.5" axle shafts and a 5 on 5.5" pattern, so I don't have to go 8 lug. Should be plenty for my 37s. Bob tufcj

mika01

Upgraded my rear as well to semi float Dana 60 HD with 35 spline Moser alloy shafts with 4.10's & Detroit 5 on 5.5 as well.

1980_Cj7

I'd rather stay full float, and don't want to hog out the spindles to fit 35 spline axle shafts. Seems like it would substantially weaken the spindles. So, the only option is aftermarket alloy shafts.

JERSEYJOE

I can't believe you broke the 30 spline Dana 60 axle. I am building a CJ 7 with a full float and stock 35 spline axles. I was going to keep the stock axles rather than spend the $$$ for alloys. I am also running a 401 with 37's.

1980_Cj7

JERSEYJOE wrote
I can't believe you broke the 30 spline Dana 60 axle. I am building a CJ 7 with a full float and stock 35 spline axles. I was going to keep the stock axles rather than spend the $$$ for alloys. I am also running a 401 with 37's.

Well we did. I just noticed a typo in the pic link on the previous page and corrected it. Maybe the pic wasn't showing up until now, but there's the proof.

Where are you guys finding 35 spline rear Dana 60's? Or, are you having them built. My understanding is 35 spline rear 60's were scarce to non-existent. Or are they all semi-float?

Was just reading on POR that the Dana 70 spindle, which takes a 35 spline axle, is the same outer diameter as the Dana 60 spindle, so maybe boring it out isn't the problem I thought it might be. But then of course we'd have to change the Detroit too, unless we could just swap out the side gears.

tufcj

My 35 spline 60 is semi-floating. Came from a late 73 or 74 J4000 Jeep truck. They had 5 on 5.5" lug patterns just like a CJ. The 35 spline full floaters are out there, but were primarily on 1 ton duallies, so they're REALLY wide. Bob tufcj

JERSEYJOE

Mine is a Dana 60 HD. Bought it on ebay. It's basically a Dana 60 center section with extra ribbing and the outer spindles and hubs from a Dana 70. It came with a WMS of 63 inches and I am running it as is. I had to machine the centers out of the H2 wheels to fit over the hubs. When I went for the rear disc kit it was a fiasco since off the shelf brackes did not work. Thanks to the guys at Street Rod Engineering for making the one off barckets to run rear discs.