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C8.25 29spline chromoly? drive line strength

4x4JeePmaNthINg

NAXJA Forum User
Location
Colorado
> do they exist?

> why do i want them? If I put alloys or such up front why not the rear.....
i want the jeep to be stout with out worrying in the Colorado mountains.
For Steep rocky up and down descents

> Can they be made if no one distributes these?

> i want a very reliable drive train that can withstand high alpine driving.

Ideal ARB rear locker with the current 3.73 31/32" largest tire, maybe a true trac upfront (hpd30) T/C is a 242. auto tranny.

the rear drive shaft has spicer u joints. Does this sound stout enough for regular moderate wheeling? When i say moderate i mean as stated above, high rocky alpine 4x4.

Im traveling alone to far reach places that i cannot afford to hope i have dependable equipment for, I wheel smart not a skinny pedal fan. I know my stock driveline has got me far but i want to really make sure its stout.

Please give your opinions and any help you can aid, thank you!
 
The c8.25 rear axle does not have ujoints. For your intended purpose I also do not think you need to install alloy shafts into the c8.25. I do not know that there is a better option for your drive shaft ujoints than spicer, and I would not worry about them either. What I will say is that with your gear ratio, I personally would not go to a bigger tire than 31's mainly over concerns about high altitude highway driving getting to and from high altitude trails.
 
I've never seen the need, this is me at Black Bear with 33's, 4.10's and a 8.25!
P1010356_zpsc3d7afd3.jpg
 
but yes, chromos for the 8.25 are readily available.

Are you sure about that? I didn't find any when I looked recently and I was told they didn't exist because the bearings ride directly on the shafts which wasn't so good for chromoly.

Everything I saw looking was the same 1541H material. Most folks claim it at +10% vs. stock shafts. I ended up ordering the Yukon shafts as I wanted to shop from a known brand and they have rolled splines rather than cut. They claim "up to 25% stronger" but claiming "up to" isn't saying much.

https://www.amazon.com/gp/product/B0078U911E/ref=oh_aui_detailpage_o04_s01?ie=UTF8&psc=1

I'm sure stock is fine in most cases but my bearing surfaces on one side spalled, so I ordered a set and I'm keeping the good stocker as a spare.

XJ_ZJbrakes4.JPG
 
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I have done a considerable amount of Colorado and Moab wheeling with 2 different XJs on 33s with a 8.25 and Powertrax No Slip lunchbox locker in both. I liked the set up so much from the first XJ that I swapped a 8.25 into the next XJ I bought. I never had an issue with the stock shafts and they both saw a good amount of crawling along with the more scenic Colorado trails.

I would never discourage an upgrade, but I think you'd be ok with it as is.

I swapped the 8.25 out when I went to 35s.
 
I've never seen the need, this is me at Black Bear with 33's, 4.10's and a 8.25!
P1010356_zpsc3d7afd3.jpg

I did black bear last month as well and no chromos are not needed for this, BUT lets say your going up and down trails similar to the BB water fall at 10-13000 ft. Heavy heavy incline/declines. eventually locked rear...

Im posting a lot on the strength of my drive line and what many have had success pushing theirs to. I have no other comparison than Colorado wheeling for what im trying to gauge the strength of axles and ujoints. Im building to not get stranded haha

to everyone else any advice or CO trails that the C8.25 29 spline and hpd30 can hold up to thanks for the info. im open to any other examples of the what these drive trains have traveresed! thanks for the pic that is very helpful!
 
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The c8.25 rear axle does not have ujoints. For your intended purpose I also do not think you need to install alloy shafts into the c8.25. I do not know that there is a better option for your drive shaft ujoints than spicer, and I would not worry about them either. What I will say is that with your gear ratio, I personally would not go to a bigger tire than 31's mainly over concerns about high altitude highway driving getting to and from high altitude trails.

having run 32 GY mtr kevlars i do agree with your concern on the highway they do bog the rpm's a bit, but they have pulled me out of some surprising situations!
 
If you're only running 31" tires a stock 8.25 should be plenty fine. Even stock axle shafts in the D30 are likely OK. Unless you wheel like a maniac. Keep a spare set of front shafts and if you start breaking them go for chromoly axles. Stock steering is going to be weaker than axles. The tie rod is the first to bend. Something like Black Bear is challenging on that approach to the first switch back because its all ledge. You're holding your brake and going slow. The next switch back or two are tight so you need multi point turns with a spotter to keep your nerves calm. We did it this summer. Imogene is challenging because the Ouray side can be an ice field in one or two spots. Other than that, you could do it in a stock XJ. The Alpine Loop has some hills you can go fast on and beat stuff up. These are just Jeep trails, not rock crawling trails. I have a Jeep with a 2.5" lift on 30's that I run these trails on...
 
If you're only running 31" tires a stock 8.25 should be plenty fine. Even stock axle shafts in the D30 are likely OK. Unless you wheel like a maniac. Keep a spare set of front shafts and if you start breaking them go for chromoly axles. Stock steering is going to be weaker than axles. The tie rod is the first to bend. Something like Black Bear is challenging on that approach to the first switch back because its all ledge. You're holding your brake and going slow. The next switch back or two are tight so you need multi point turns with a spotter to keep your nerves calm. We did it this summer. Imogene is challenging because the Ouray side can be an ice field in one or two spots. Other than that, you could do it in a stock XJ. The Alpine Loop has some hills you can go fast on and beat stuff up. These are just Jeep trails, not rock crawling trails. I have a Jeep with a 2.5" lift on 30's that I run these trails on...
Ive got a moog zj drag/ tie rod and RE trac bar. I as many do am continuing to get into more aggressive trails and Ide rather be prepared then break and find out i was not set up for the trail. Granted there is only so much 31/32s will tackle but with no lockers and still going for it i always wonder if these shafts and ujoints will hold... I wheel smart but a 33x10.50 would be ideal in the future so ide like to plan accordingly.
 
I ran 35X12.5s and didn't have an issue for two years till I stayed in the throttle and cracked the carrier/grenades the welded spiders.
fe72696a1ebd9277798cf3b346bca19f.jpg
I broke more parts on my Dana 44 than the 8.25

Sent from my 0PJA2 using Tapatalk
 
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