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1986 jeep cj7 with a 258 4.2 bored 30 over. 4 inch suspension lift and 1 inch body lift. When completely done it will be camo wrapped and have bumpers,winch,33s or 35s,a double outlet header and performance carbeurator.
Will an AMC20 move 35s through some mud and over rocks pretty well? I dont want to tear anything up on my jeep but 33s will look small on my jeep. Please give me some advice.
1980 CJ7 , AMC 360 with a TBI, T-176, Dana 300, full float Dana 44 rear with spool,1983 Dana 30 wide trac with lock right, 4.88 gears and alloy shafts all around.
1986 jeep cj7 with a 258 4.2 bored 30 over. 4 inch suspension lift and 1 inch body lift. When completely done it will be camo wrapped and have bumpers,winch,33s or 35s,a double outlet header and performance carbeurator.
1986 jeep cj7 with a 258 4.2 bored 30 over. 4 inch suspension lift and 1 inch body lift. When completely done it will be camo wrapped and have bumpers,winch,33s or 35s,a double outlet header and performance carbeurator.
1986 jeep cj7 with a 258 4.2 bored 30 over. 4 inch suspension lift and 1 inch body lift. When completely done it will be camo wrapped and have bumpers,winch,33s or 35s,a double outlet header and performance carbeurator.
They will. It addresses the two main problems. If you want to go jumping, that's another issue. Some people do add a truss though. You can still break them if you want to.
1986 jeep cj7 with a 258 4.2 bored 30 over. 4 inch suspension lift and 1 inch body lift. When completely done it will be camo wrapped and have bumpers,winch,33s or 35s,a double outlet header and performance carbeurator.
They will. It addresses the two main problems. If you want to go jumping, that's another issue. Some people do add a truss though. You can still break them if you want to.
3.54's are a little high for 35" tires. You will probably want to go to at least 4.10's. That is what I run with a three speed auto. Mud out here is in short supply, and you NEVER power through it due to hidden rocks and logs. I always drive my Jeep like I have to drive it home, because I do. Less throttle, more finesse.
1986 jeep cj7 with a 258 4.2 bored 30 over. 4 inch suspension lift and 1 inch body lift. When completely done it will be camo wrapped and have bumpers,winch,33s or 35s,a double outlet header and performance carbeurator.
3.54's are a little high for 35" tires. You will probably want to go to at least 4.10's. That is what I run with a three speed auto. Mud out here is in short supply, and you NEVER power through it due to hidden rocks and logs. I always drive my Jeep like I have to drive it home, because I do. Less throttle, more finesse.
83 CJ7 350 tbi, TH350, D300 twin sticked & clocked, narrowed Chief D44 Eaton Elocker & Moser shafts, Explorer 8.8 Detroit locker, 410's, RE 4.5" spring lift 1" body lift, 35" Claws, cage tied to frame, Corbeau baja seats, HD tie rod and draglink, u-bolts flipped, custom skid plate and sliders, Warn 9.5ti winch with Amsteel synthetic line
Here's my 2 cents. I ran my 20 for about 5 years with 33 and 4:10 gears, Detroit locker.
I than changed to 35's and broke it in about 1 year.
I spun a tube. (Welding them might have stopped that.)
I bent the opposite tube at the same time. (A truss might have stopped that.)
I also twisted a Superior axle spline (1 piece axle)
I run mainly rocks which I think is easier on equipment than mud having done both in the past.
So I say stay with 33's and your be safer in the long run.
I also had to trim my fender wells to run 35's (4" lift plus 1" body lift) so keep that in mind.
I also agree that you need at least 4:10 gears for 33's and 4:56's or 4:88's for the 35's.
1979 Jeep CJ5 with 304 V8, T18 Transmission, Dana 20 Transfer case with TeraLow 3:1 gears, 4.88 axle gears, Detroit Locker up front and Ox Locker in back with 1 piece axle shafts, 36" SuperSwamper SX Tires, Shackle reversal, MileMarker Hydraulic winch, MSD 6A ignition.
I run 36 inch tires with one piece axles in an AMC20 . I have 4.88 gears. I think you need one piece axles for almost any tire size on the AMC20 . The 2 piece axle shafts are the biggest weakness. In hind site I wish I had Dana 60's. I don't take the hardest trails as much as I would like because of my axles. BUT you can give an AMC20 a lot of abuse with one piece axles.
The AMC model 20 is weak because of the hub being keyed onto a tapered shaft ( I just sheared the key in my 80) a solid axle is the way to go. Welding the tubes and a truss would be good too if you really plan on getting crazy off road. The key to a good working model 20 is making sure the torque is correct on the castle nut on the end of the axle is correct (I think 250 ft/lbs) After mine broke I noticed at disassembly that it was barely hand tight! So if its working now, at a minimum I would pop off the little dust cap and check the torque on the axle nut. Ten minutes for a little piece of mind good luck
1986 jeep cj7 with a 258 4.2 bored 30 over. 4 inch suspension lift and 1 inch body lift. When completely done it will be camo wrapped and have bumpers,winch,33s or 35s,a double outlet header and performance carbeurator.
I run 35's with a AMC20 w/4.56 gears, 1 pc axles, welded tubes, and locker. You can run em with a higher gear but at least 4.10 and then your going to have take care and not push it. I play on some rocks here so I take care and slow crawl
To get the benefit of the 35s you are going to have to change out the R&P and very possibly the differential, the tracklock is a bit better than the open but if you have more than 100k on it the clutches were worn out a long time ago and you don't have the option of using a drop in locker into it, so the rest of the axle is relatively cheep to replace after that. You could upgrade to anything from a Dana 44 to a ford 9".
In my opinion, axles are all about the money. decide what ratio you want and what differential and see what is most cost effective. the only reason I replaced the AMC20 was it was cheaper to go with the Dana 44 that I did not have to buy axles for.
I start by seeing if I can make a decent highway speed at 2000-2500 RPM (power peak for AMC 258 i6 / 4.2l ) @ 1:1 high gear with the tires of choice. you have not filled the profile very well so I have no idea what Transmission you have 4 speed/5 speed. and what Transfer Case , low 4 ratio.
if you have not looked at this Gear Ratio Calculator
please do, it is very interesting. from what I see you could almost get away with the 3.54, if you have a 5 speed you more than likely won't be using 5th much and I would think merging with highway traffic could be a bit exciting sometimes.
IOs second law:
Nothing is ever as easy as it first looks.
One piece axles are a must on the corp20...no question about it. Your gear ratio is going to be an issue with 35's, even 33's, so consider re-gearing.
I run 36's on my corp20 with 1-piece axles and 4.10's...that is a bit higher geared than I would like, but with 430hp and a compound low T18a, it more then suffices.
So yes, the 20 can be made strong enough for larger tires and even some horsepower, a bigger concern is the front Dana 30 . I've broken more shafts then I can count and upgrading to larger U-joints is heavily recommended. The problem with this however, is it moves the weak point to the R&P if your hubs have been upgraded.
