Rear Axle Question

All this talk about axles on here has me wondering something. I want to beef up the rear axle on my 69 cj v6. I already have the dana 30 and both sets of leaf springs out of a 93 YJ, and I kinda broke the bank on it and paid a little more than i wanted to. What kind of upgrades can I do for my rear axle under say........600 bucks?

 

The best upgrade is going from a tapered two piece axle to a flanged 1 piece axle. That makes a stronger shaft and upgrades from 19 spline in your case to 30 spline which is much stronger. That's assuming you don't already have a flanged axle. You can upgrade to the 1 piece axles but I think it was around $700-$750. I think it was Scott Milliner that went that route. You could also build a Full floating axle but you're gonna most likely be in it about the same. It's really easy to add disc brakes to the rear if you go with a FF kit. You could add a Powerlock limited slip which gives you a "posi" unit. These are stronger as they have 4 pinion gears and two pinion shafts which is double what an open case or trac lock limited slip has. These are not a locker but one of the but one of the best limited slips ever built. All the manufacturers have used it in one form or another over the years. Best of all they could be ordered in Jeeps. If you have a tapered axle now you might find an offset flanged axle from a '70-'71 CJ and start from there. You would most likely be money ahead. You can't take stock flanged axle shafts and slide them into a tapered axle as the housing ends are different. The flanged offset CJ axle is a direct replacement for the tapered axle diff, comes stock with 10" brakes already, and has larger and stronger axle tubes. Nickmil

 

I've been going through the same ordeal with my rear axle. The couple options I have come across are the following:

Contact PartsMike (he has a website, but call him, he is very helpful) and talk to him about getting 1541H flanged, 30 spline conversion axles from Dutchman for your rear end. This will also require changing out the carrier to accept 30 spline axles, but changing to 30 spline flanged will be significantly stronger than the 19 spline non-flanged we have right now. I only use my jeep off-road and for rare around town fun, so I will put a spool in my rear end when I do the axle shaft upgrade. For the Dutchman axles and the 30 spline spool the total comes to about 600 bucks, which is right in your price range.

The other option is to talk to Summers Bros. about getting some 4130 flanged, 30 spline conversion axles for your rear end. The 4130 will be significantly stronger than the 1541H, but both will be much stronger than stock. The Summers Bros. option will be your strongest option, though, but at the price of running almost 700 bucks for the axles plus the cost to change your carrier over, which if you use a spool will be another 200, puting the grand total of this option to 900 bucks.

Personally, if you are going to wheel the thing much and have 33" or larger tires, I would just save up the extra 300 bucks and run option 2. I believe that is what I will do. Go most extreme first time and never look back (to see a broken rear end, hehe). Anyway, let me know if you need anything else, or want further info. I know it is a long post, but it seems pretty straight forward.

 

thanks for the advice so far, I guess I should have clarified that this vehicle is a daily driver and sees trail time a couple times a month at most. I'm new at all of this, as I've said many times. But I between a friend who is a good mechanic and what I've picked up off this site hopefully I can have the D30 and springs in one weekend, and try to switch out to a flanged axle another weekend.

For those who have done the D30 and leaf spring swap was there anything you learned from the swap that might save me some time and/or headache??

 

If your D30 is out of the '93 YJ you are gong to have a width issue.

 

Oh no.....well I haven't paid the guy yet, just gave him my word on it, maybe he'll understand it won't work. I can still use the leaf springs though. What model do I need to look for a D30 out of???

 

'72-'86 CJ. around '82 they went wider but will work. Many feel the wider axles are an upgrade over the narrower due to better turning radius (the tires less likely to hit the frame and springs). Nickmil