ATLAS 4 help!!! lol

[Rock_Crawler_97]

Hello everyone... Am new to this and this is my first time posting. Y'all seem pretty good at solving problems, so hear i am... Actually i need Advice.

First let me start off by saying what the project is...

My project is a 97 TJ with a 4.0 Orgnially it had a 5 speed, but i converted it over to a 2001 cheeroke auto. Than put a dana 300 with a flip kit. It has a dana 30 up front with and ARB and chromoly axles. The rear consist of ford 8.8 w/Detroit and 4.88's. It sets on 37/12.50/15 MTR with a 5.5 Rubicon long arm, ACOS adjusters, and a 2in body. Front steering has Krawler X-factor tie rod and drag. (hym joints)

Now, am getting rid of the Dana 300 (which am selling if anyone is intersted)and installing the Atlas 4. I already have it in place, however the problem am worried about are my drive lines lenghts and how much of a problem will i have... The cheeroke tranny is longer than the normal TJ tranny. Than the adapter to the Atlas didn't help... not to mention the length of the Atlas.

The front drive line has to be extended 5 inches and the rear is what really worries me... at ride hight from center cap to center cap of each yoke it is roughly 13 inchs give or take... I was always told the longer the rear drive line the better...

How bad is this shorty going to effect my crawling?

I think a stretch kit will work awesome and allow me to use my current drive line, but with the money i spent on the Atlas 4, its going to have to wait till next year. At the same time thou i don't want to be without my jeep for that long, so will that short rear driveline effect me real bad?

Thanks for any help and SORRY for the long post.

[ECV Jeep]

I had the same type of issue, in that with the 4 speed my rear axle drop would bind the double cardan joint. For over a year I ran a single limit strap from the top of the diff to a frame mounted cross member I fabed up. That allowed me to limit the drive line angle and still allow a fair amount of articulation at each end of the rear axle. It was not optimum, but it did work pretty well.

Ultimately, I went with the stretch kit to solve the problem.

[inVERt'D]

No doubt others here could give you better advice than I could, but here goes anyway. Obviously, the real problem isn't the length of your driveshaft, it's the sharp angle created by the combination of your ride height and the short driveshaft. Someone may beg to differ, but I think the combination of your short driveshaft, high ride height, and rear long arm sound like bad juju.

With a CV type driveshaft, the pinion on your diff will be parallel with your driveshaft, so that u-joint should be ok, depending on how droop affects your pinion angle, which is determined by your rear suspension setup. Not being too familiar on how RE long arms cycle, I'll leave that to others. Anyway, the u-joint that will be at a sharp angle even at normal ride height will be the forward one, right up against your pricey Atlas IV (I didn't even know there was an Atlas IV). I would expect that to be problematic, both with driveline vibration if you actually drive this thing at road speeds, and with torque stress on the u-joint. As much as that long arm can droop, I think the angle on that thing could get real severe, and that's when I would expect binding and breakage. That's also uncomfortably close to your Atlas. Even if it is "bullet proof," that could put a lot of stress on your output shaft; vibration can do bad things too.

I don't think your RE belly plate gives you a lot of room to lower things, so I can think of several things you can do: 1) move your rear axle back; 2) lower your Jeep; 3) angle your engine, tranny, and transfer case down.

1) I'd adjust your rear control arms until your pumpkin is close to hitting your fuel tank skid. If you're still using the stock skid, I'd take a BFH and make some more room and stretch it even more. You should be able to get at least another inch or so. There are fuel cells that go fairly cheap on eBay too...

2) Not sure how much you can lower your rig the way it's set up and still clear those 37s, but I've seen a rig with stock springs, a 1" BL, and tubed out clearing 40s. He actually removed his fenders and ran a high-clearance fiberglass hood. For the rear there was obviously cutting involved.

3) This one may work in combination with other solutions, but it's not going to work by itself.

[inVERt'D]

Just saw your limit strap post, ECV Jeep; yeah that could help things from getting too crazy.

[ECV Jeep]

One other thing I would highly recommend with the 4 Speed is the Roark Fabworks Atlas Support ring. You will need to fab a cross member to hold the ring, but the ring will support the tail shaft housing of the Atlas. As you know, the 4 speed is a big, heavy case and I was never comfortable with all that weight and length hanging off the tranny. For about $100 bucks, the support ring is cheap insurance.

Call Travis Roark. Roark Fab Works Olive Hill, KY 41164 606.286.0681

You can find several articles and posts about the benefits of this item.

[Britain]

Been running my Atlas 4 for about 3 years. I'm high , steep angle run the dog snot out of it. Nada nothing broke, ripped apart yet....

[Don Davison]

I put a high pinion 9 in rear no issues with driveline angles

[inVERt'D]

Doesn't sound like he can afford a hi 9 now.

[Rock_Crawler_97]

I don't think your RE belly plate gives you a lot of room to lower things, so I can think of several things you can do: 1) move your rear axle back; 2) lower your Jeep; 3) angle your engine, tranny, and transfer case down.

1) I'd adjust your rear control arms until your pumpkin is close to hitting your fuel tank skid. If you're still using the stock skid, I'd take a BFH and make some more room and stretch it even more. You should be able to get at least another inch or so. There are fuel cells that go fairly cheap on eBay too...

2) Not sure how much you can lower your rig the way it's set up and still clear those 37s, but I've seen a rig with stock springs, a 1" BL, and tubed out clearing 40s. He actually removed his fenders and ran a high-clearance fiberglass hood. For the rear there was obviously cutting involved.

3) This one may work in combination with other solutions, but it's not going to work by itself.

Thanks for all the advice.... I was already planning on sliding the rear axle back. I have a Kilby plate over my gas tank, so from the looks of it i might get an extra inch at most. I plane on lowering the front 1inch but as for the rear, its as lowest as i can get it and it rubs already. I hope these two thing work. What's the most damage u think can be done? if i ran it like that...

Also thanks "ECV Jeep" I did observe that same thing and fabbed a rear bracket for the back to give it some more support.

If by some maricle i sell some of my items or extra vehicles i have... Which Strech kit would y'all recommend that will give me the best bang for the buck...? remember am poor here... lol
As for the high pinion... yea way out of my budget. Heck i still need a front axle... tiny little 30 is bound to break lol Plus i figure i would leave the ford 8.8 till it breaks lol

[Britain]

I run a D60 high pinion, broke off the shocks and everything else yet still havent damaged the 4 spd.

its fugly under my junk but hey it still works!

[xjkevin]

pm sent on the 300