5.13 & 37s VS 5.38 & 40s

dillard09

New member
So I have done some searching and Im sure that it has been asked before but I didn't see it.

So here I am with stock Rubi axles, 5.13, 37s, and DTD. I feel now that I can push my rig but im worried about my axles not holding up to what the DTD can dish out. My wife and I with our new son like to take the Jeep everywhere. So I want to be able to be comfortable on the road as I am offroad. Be able to wheel the rocks, bomb the fire roads, and be comfortably driving home. That being said, I know how the 3.8L (Low Output) is with 5.13 and 37s. I can use cruise at 65 but if I hit any kind of angle, I have to hit the OD button. I have 45,000 miles on the 3.8 and not looking to do a motor swap until it shits the bed. So here is what I was thinking...

PR44 front and PR60 SF rear and stick with 5.13 and 37s. (Cheaper route but solid for 37s)
PR60 front and PR80 FF rear with 5.38 and 40s. Way more expensive but the last axles you will have to buy.

For those that have ran both setups w/ the 3.8L (Eddie) how do the two compare as far as drivability? I know offroad the 60/80 combo and 40s is superior but I would like to be comfortable on the road too. (For the wife and kiddo of course). I have seen the charts for tires size and gears and what rpm you will have at 70mph. It says that the 5.38 and 40s is about 100rpm less than 5.13 and 37s. Is that a huge difference?

I know the price difference is way different for the axles and when you factor in wheels and tires too. But I can just save a few more months. I just want to do it once and be confident on the trails and be able to hop in the Jeep and drive 1000 miles comfortable.

Guys I appreciate you help and honesty.
 

jkwebbie

New member
Honestly, I have no experience with either because I'm going a different direction with my axles. But if it was me, I would just got with 60s front and rear. You really don't need a 80 rear unless you plan on throwing in a Hemi or LS motor too. But even then, a 60 rear can hold a V8 motor pretty good.

Also is your Jeep an auto or manual? If its a manual I would stick with 5.13s but if auto go with 5.38 would be better.
But hopefully some one else that's done this can help and chime in. Congrats on the upgrades man!
 

dillard09

New member
It is an auto. That's the way I am kinda leaning right now but still on the fence. Money is not the issue so 60s would be awesome if the end result is something I can deal with at 65-70 in the 3.8. I just know now with the 37's and 5.13 on a road trip I have to do quite a bit of driving without OD. Not a big thing in the whole scheme of things but at 3-3300 rpms it does get loud with the exhaust.
Or should I just stick to 37's and drop that extra cash saved over the 60s and new wheels in something else like the EVO hi clearance long arm upgrade?
Or go 60/60 with 5.38 and 37s. That should put in a better rpm but why would I go 60/FF and stay with 37s when the PR44/SF can handle the 37s? Atleast I know what I get with 37s and 5.13.
I have been racking my brain with this!
I know most don't care about what it's like on the highway.
 

ChaosNein

New member
5.38s with whatever axle setup you decide on and whatever tire you end up running.

You just need to decide if you want to spend 12k or 20k.
 

dillard09

New member
I was hoping you would chime in Drew. Thanks for getting the rig ready for Colorado. The trip to Colorado was awesome but not without its issues! So the clockspring issue got worse, ding every couple minutes! Drove me crazy! I had that changed in Montrose, CO by Alpine Offroad. BTW Terry the shop owner is a great guy and had nothing but good things to say about ORE and Mel. The new wheel speed sensor turned into a wheel bearing being changed on the side of the road in Pitkin, CO. Now I have ball joints with a little to much play. The passenger side front axle seal is leaking. And I worked the rear bumps stops out pretty good. Time for the King bumps back there. The drag link tie rod end nut on the passenger knuckle backed off some causing lots of play in steering. BTW it was coming down Black Bear!! Had to tighten that up and straighten the steering wheel.

So im ready to go up to something bigger and better. If I go with the PR44 and 60SF it wont be with the 5.38s. If I go with the 60/60FF then yes.
I also was thinking of the Hi Clearance long arm and hydro assist when I come in. So the price tag could be up there!!
 

dillard09

New member
$20k goes way too quick. I've spent that just on the dtd suspension and the much cheaper Mopar/Spicer dans 60 axles. Still need literally everything else.

I know everyone has their opinions on the UD60, but what do you think of them?
What does ORE think of them, Drew?
 

highoctane

Caught the Bug
I know everyone has their opinions on the UD60, but what do you think of them? What does ORE think of them, Drew?
I haven't installed them yet. But looking at them in the crate they look super beefy, but the paint job on it looks like spicer doesn't put near the pride and time into these axles as Dynatrac does. Sloppy paint job where they literally painted over everything. It does come with 4340 chromoly 35 spline 1 1/2" axle shafts in both axles, and up front has Warn 35 spline Premium hubs, but it still has half circle clips on the 1550 front u-joints, but they are 1550 joints, absolutely huge.

I definitely went the cheaper route on axles. No doubt the Dynatrac axles are superior. But I'd have had nearly as much in a front pro rock 60 as I have in the full set of Mopar 60s. I got a good deal on mine from the local dealer. If my budget allows it I still might go with dynatracs and sell these axles for a small gain or worst case, just for what I paid for them.
 
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dillard09

New member
I have yet to see them in person. I know you can get the UD60 for 10,900. But is it a middle option between PR44/PR60SF and PR60/PR60FF?
We all know that Dynatrac puts out a superior product, stands behind their product, and values their customer.
 

dillard09

New member
Well my son is only 14 weeks old, so I have to do it now before he starts taking my money and wanting to borrow the jeep.
 

Jk909

New member
I know. I was thinking the same thing then Drew had to go off and tell how much a difference 40s are and it got me to thinking! Dang him!

If your already running all of the trails that you like then there is no need. I could understand if your tires are a limiting factor. All I'm saying is don't go for 40's because they're cool.
 

2Cross

Caught the Bug
I had this dilemma about 3 years ago.
I went with PR44 front/PR60 rear.

Not sure if what I say matters. But I'd go all out if I did it again. 60/80.
My budget couldn't do it then or now.

Good luck with the sale of your son!
 

dillard09

New member
If your already running all of the trails that you like then there is no need. I could understand if your tires are a limiting factor. All I'm saying is don't go for 40's because they're cool.

I hear ya and thats what I thought too. The more I wheel the more I want and the harder I want. I just don't want to go with the PR44/PR60SF and stay on 37 and then regret it later. But I also might want to drive it to Montrose, CO and hit Die Trying and Cactus and then drive back with the cruise control on. I'm just saying! But then again I'm sure the PR44/PR60SF and 37s would be sufficient for most of my wheeling.
 
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