Hmm...

So judging by the responses so far, it looks like the silent majority are not upgrading their driveshafts when going to 37s - unless the cost was so high they don't even want to talk about it! ;)

I suppose I could put the thing in the air, drop the shaft first, and make a judgement call on my own as to the expected life of the factory boots. I've seen some pics of people doing what looks like serious offroading on 37s, and they haven't posted info about upgrading their driveshafts. So that's a check in the 'do nothing' column. However, I don't want to be stuck somewhere google maps can't find, and dry my tears with a busted boot.

I guess the other thought was that a _longer_ driveshaft or two might be needed for a lift of 4" or more. Again, I haven't heard anyone say longer 'shafts are needed, so I'm taking that as a "no". Since I'm new to some of this, I'm not entirely sure how longer control arms make up for a more diagonal driveshaft position (which would bring the axle closer to the center of the vehicle). I'm not big on buying a bunch of parts, closing my eyes, and hoping for the best - unless it's not my ride! :rotflmao1:

still learnding,

-a2kl

The only reason I see if putting new driveshafts on would be for a longer slip yoke. A replacement shaft will have the same u-joints that are in the now so whats the point. The rear shaft is long enough that a special CV shaft isn't nessesary.

Thanks, but we are not on a tangent. Those are driveshafts.

Because of the way the suspension works, there actually isn't that much of a need for a longer shaft unless significant geometry changes are made. When the axles drop down, they swing toward the center of the vehicle. This is different from leaf springs with shackles on the outer ends, which almost always make a longer shaft necessary.

just to clearify what I am talking about
http://project-jk.com/gallery2/main....serialNumber=2
the top on is a u-joint something you can find any where the bottom is a cv-joint
I have 4" lift and running 37"s and I am going to upgrade

Bonedigger- be sure to post what you get. I will be upgrading mine as $ permits... Especially since I have already torn the front boot. If no one has noticed yet, the front driveshaft u-joint doesn't have clips. The joint is pressed in and the yoke "punched" to retain it.

that is what the guys at six states called a fixed u-joint and I will be replacing that also

evolution guy's= always right!!!
 

If the guy's from Evolution are giving advise...take it. These guys know their shit and they know from experience. They've been there and done that. Thanks for your feedback fellas! You have definitely helped me with my Project JK over the phone. Big props!!!

What???
 

Wrong... 4" inches or more means YES! There are two words being thrown around alot "Recommended" or "Required". They are being thrown around lose-ly. There is a big F-ing difference. Im trying hard not to sound like a dick. But speaking from experience those two word have screwed me in the last 3 weeks!!! I have a 5" Skyjacker Lift, 1 Inch M.O.R.E. Body lift and im running 37's. Also I have replaced both drive shafts with JE Reels 1350 set for front and rear. Why invest all this money into a brand new vehicle and do it half-ass. Because in the long run you will do more damage to other parts and will eventually cost you more money. If you want to cut costs for now... than dont by the bumper, winch, seat covers, etc... spend the money where it counts. If you want the real scoop call the guys at Evolution. Who am I? No one special! But think about it... its your driveline your talking about. You don't have shit without it!!!

can i use my free spin?
 

Many interesting things in this quote:
1. There's no right or wrong answer for posts in this thread. I'm just asking what have people done, and my reply was based on the responses so far. Whether what they have done is right or wrong isn't up for debate (at least not in this thread)

2. You mention two words being thrown around, and then you throw them around yourself, without mentioning which word is the correct word, in your experience. Yes, you did the upgrade. But w/o the upgrade, were putting 37s on your machine impossible? If so, that would be helpful. If not, that would be helpful too. Even if you (or an expert) don't advise going a certain route. It sounds like not upgrading almost bit you in the butt - why? Did you order everything else and then find out it wouldn't work w/o driveshafts? Something else? If it's been a 3 week ordeal, I'd like to hear the story.

3. You quoted my quote, which already stated that people with 37s on right now have yet to post "yes, I had to upgrade, impossible to do 37s w/o driveshaft upgrades, and they cost me $x" - yet you seem to have 37s, but don't really answer these questions for the thread. I know you DID upgrade your driveshafts, but the two important questions are left unanswered (saying that you didn't want to do something half-butted doesn't really count - everyone wants to do it all correctly, the question is whether or not you can ride around for a while (which seems to be yes) before EVENTUALLY getting driveshaft upgrades).

4. You are running a 5" suspension lift. It would be nice to know if 3", 4", or 5" or some other number is a number where _no one_ is using their factory driveshafts. That would be a telling stat too. Example: If someone is running a 2" lift, there's no need to upgrade your driveshafts UNLESS you want a more rugged set of parts. This is not the same issue originally posted in this thread. But I do know now from this thread that the "required/recommended" line is blurred at 4" because of the potential issues with the driveshaft angles and boots.

Yes, I agree, hearing from the Evolution dudes carries some weight - pun intended. But hearing from others (including you) who have been out on trails with or without new driveshafts is great too. Just trying to find out what everyone's doing, because I see lots of 37s, but not many people listing driveshafts on their list of "stuff they did" to their jeep.

-edit- I also see you have a 2 door jeep, so I'm not sure why you've posted a reply to this thread at all. :thinking: -edit-

-a2kl

I bought my Jeep to go "OFF-roading!" It is not a daily driver for me. So I am building it to stand up to anything. Im sure you can drive your Jeep back and forth to work and not have a problem with the stock drive shafts. All the experts that make the lifts say any lift over 4" require driveline modifications. Its not coming from me. So I believe the right answer is yes... you do need it. I didn't throw any words around. I did the upgrade because the people that designed my lift told me I would need it! It is similar to the TJ when it was required to use a slip yoke eliminator. Bottom line it is required by the lift companies. Call them and ask them. Ive done far more research than most on this forum. My knowledge is coming from me... its from the people who build this stuff for a living and they are damn good at it. I agree there are differences in some of the mods on a 2dr verses a 4dr. You sound like a smart guy. I know im not. You'll figure it out...see you on the trail... maybe! :naw: