Question: I'm new to four-wheeling, and I have an '00 Jeep Cherokee that I am going to lift 4 1/2 inches. I was wondering if I have to get a slip-yoke eliminator? I was also wondering if I have to change my steering column? Is a 4.10:1 gear ratio good enough to run 33x14 Boggers?
Robert Dodman
via fourwheeler.com
Answer: No, you won't have to do a thing to the steering column. The 4 1/2 inches of lift just may be marginal without the slip-yoke eliminator kit. I think that I would put the lift and tires on and see just how far out of the end of the transfer case the driveshaft rides. It will be out quite a ways from stock and just may not have enough engagement, so you may need to have a longer driveshaft made. The real advantage of the slip-yoke eliminator kit is that it gains you a driveshaft several inches longer, which in turn reduces the angle at which it operates and will hopefully prevent any binding of the U-joints.
I suggest that you jack up the rear of your Cherokee by the rear bumper until the wheels are hanging free. You did block the front wheels on both sides to prevent the Jeep from moving, right? OK, now crawl under it and turn the driveshaft by hand, paying close attention for any U-joint bind. If it does bind, then you're a candidate for the kit. It's going to require a new driveshaft with a slip-yoke built into it.
If there is no binding, still consider a longer driveshaft so that you'll have a good positive engagement with the present slip-yoke that slides inside the transfer case. It's important to make sure that it is not too long so that at suspension compression, the end of the yoke doesn't bottom out and put end pressure on the case.
Using a 4.10:1 ratio will put it back pretty close to what the overall ratio was when the vehicle was stock. You will feel some performance loss because of the added rolling resistance of the larger tires. If you're going to see a lot of off-pavement travel and not as much highway with the Jeep, then 4.56:1 would be a much better ratio. Perhaps this would be my choice.
Question: I have a '92 Wrangler YJ with a Skyjacker lift and 35x12.50-15 Baja Claws. It has the original differentials, and I recently acquired a set of Dana 44s from a '76 Dodge which was full-time four-wheel-drive. I did not, however, get the transfer case. I want to lock it up but have heard so many different things about which lockers to use and whether to lock the front solid. They are both posi units-is that good enough for the front?
I play in mud, snow, and hillclimbs, and would like an all-around good machine. I've heard that locking it up all the way around makes it hard to handle in the snow. I live in Oregon, so the snow is wet and heavy. I didn't want to spend the money for selectable lockers, but is there any other way? Right now, it has the stock 4.0L and manual tranny and transfer case. A small-block Chevy will be added as well as an automatic. Can you recommend a transfer case, and are the Dana 44s stout enough to handle a set of 39x18/15 Boggers? I am leaving the axles full width since the tires rub on the springs now.
Justin
Molalla, OR
Answer: There is no reason why you can't run your present NP231 transfer case, even when you make the Chevy engine swap, and leave it in the two-wheel-drive mode when four-wheel drive is not needed. Why don't you try it with the present limited-slip differentials and see if they offer you the necessary traction for what you plan to do with your Jeep?
For snow driving, my favorite combination is a Detroit Truetrac up front and some type of a selective locker in the rear like an ARB Air Locker or the Eaton E-Locker electronic differential. Another good choice would be the Detroit Electrac which offers the advantage of the Truetrac but can be totally locked with the flip of a switch.
The Dana 44 axles will be marginal with a set of 39-inch tires, but maybe with a light foot they will survive.