Locker / Posi combo for trail rig

[dell30rb]

1997 XJ, bought to build into a trail rig. I am about 90% done with fixing all of the leaks and mechanical stuff. Full set of barnes frame stiffeners, steering box brace just showed up.

I have a matching set of waggy 44's for it. Going to install front long arms, lift 5.5", 35" tires. Use will be maybe 25% around town, 25% more difficult trails, 50% easier trails and camping with family. I have a trailer for it. Might do an occasional highway trip with easy wheeling on one side of it (I want the trailer around if I am doing anything that could break shit).

Will regear the axles and install some sort of traction device in both. Right now I am thinking detroit locker in the rear, true trac in the front. I don't really want the complexity of a selectable locker. I'd go lockers in both, however i've heard that with a front locker, it will have a very hard time taking tight turns under power in 4wd. I figure the truetrac front and detroit rear would be a good compromise, it should steer just fine in the tight stuff.

Opinions wanted! Also what gears, 4.56 or 4.88. I do not plan on going bigger than 35's.

 

[Cervelorod]

4.88 seems great with 35’s, even better with the 33’s I just put on, I haven’t had it on the freeway,in town it’s great.

 

[Phil]

I’m a big fan of locker in the front. It does not push through turns like a rear locker does. The front locker pulls you into the turn.

4.88s is nice, especially with a bigger gear set than D30.

 

[dell30rb]

I’m a big fan of locker in the front. It does not push through turns like a rear locker does. The front locker pulls you into the turn.

4.88s is nice, especially with a bigger gear set than D30.

Yeah I am wondering if I don't have this backwards. Throw a detroit or grizzly in the front and a truetrac in the rear.

 

[Tim_MN]

My 2000 is locked front and rear, no pushing. I would say locker on the rear axle because you want the benefits of the weight transfer to the rear axle going up stuff.

Locked in front on snowy/icy pavement is borderline dangerous in 4x4, TrueTrac is the best for that.

Does TrueTrac have a tire size limit?

One of the guys in my local 4x4 club has TrueTracs front and rear in his TJ Wrangler. He has no trouble keeping up with the other Jeeps with lockers.

 

[Paradiddle]

I would lock both ends - my vote is a selectable locker. When you need lockers, you need lockers.

 

[dell30rb]

Auto locker in the front, true trac in the rear and the teraflex 2wd low kit for the 231 is what i'm thinking now.

 

[JonnyCat63]

I would not do a Detroit in the front. On my 3 built XJ's, I have a Detroit in the rear, and an Eaton E-Locker in the front. It's a great set up, and the wiring for the E-Locker is easy to do. It is harder to turn with the front locker engaged, however, I rarely have to use the front locker at all. Most every time I'm in either 2wd or 4wd. I only use the front locker when I need a little extra oomph. Most of the trails I do are in SoCal. For example, I've done Gold Mountain in Big Bear a few times in each rig, and have never used the front locker on that trail. YMMV.
For me, a Detroit in the rear, and a selectable up front is the way to go. I would not want a Detroit up front. It's going to have very bad manners on the street.

As far as gearing goes, I'm running 4.11 with 32" tires on 2 of the XJ's. On the other, I'm running 4.56 on 33's, and that one has a 4:1 TC in it. All have long arms and about a 4-5" lift. All perform about the same. They are mostly trail rigs, but do see the pavement when traveling to and from wheeling sites. You're not breaking any land speed records with the gearing I have. With that being said, I almost think I could have gone with 4.56's on 32"s, and 4.88's with the 33's.

Definitely 4.88's with 35's. But with 33's and up, plan on cutting the fenders.

 

[dell30rb]

I would not do a Detroit in the front. On my 3 built XJ's, I have a Detroit in the rear, and an Eaton E-Locker in the front. It's a great set up, and the wiring for the E-Locker is easy to do. It is harder to turn with the front locker engaged, however, I rarely have to use the front locker at all. Most every time I'm in either 2wd or 4wd. I only use the front locker when I need a little extra oomph. Most of the trails I do are in SoCal. For example, I've done Gold Mountain in Big Bear a few times in each rig, and have never used the front locker on that trail. YMMV.
For me, a Detroit in the rear, and a selectable up front is the way to go. I would not want a Detroit up front. It's going to have very bad manners on the street.

As far as gearing goes, I'm running 4.11 with 32" tires on 2 of the XJ's. On the other, I'm running 4.56 on 33's, and that one has a 4:1 TC in it. All have long arms and about a 4-5" lift. All perform about the same. They are mostly trail rigs, but do see the pavement when traveling to and from wheeling sites. You're not breaking any land speed records with the gearing I have. With that being said, I almost think I could have gone with 4.56's on 32"s, and 4.88's with the 33's.

Definitely 4.88's with 35's. But with 33's and up, plan on cutting the fenders.

Appreciate the input. I am not worried about the street manners with an auto locker in the front. I have waggy 44's with manual front hubs. Any time i'm on the street those will be unlocked. Also with the tera 2wd low range installed I will have shift on the fly between 2wd-4wd in high or low range, so even if I have the hubs locked I can always put it in 2wd and the front auto locker is out of the picture, just freespooling and clicking.

I'd go selectable in the back but I want to keep it simple and I know the true trac is a durable, very tight positraction that does not wear out. I know the conventional wisdom for years was to put a detroit style auto in the rear first, but I think that has changed somewhat. My understanding of the auto in the front is that turning can feel squirrelly in the steering with it engaged but it does not hamper your turning radius on tight corners. While the rear auto would be more a stable feel, but does hurt turning radius.

Check out this video from Currie where they demonstrate a turn with a front detroit locker and rear e-locker both engaged and disengaged. The rear locker really kills the turning radius.

 

[JonnyCat63]

Check out this video from Currie where they demonstrate a turn with a front detroit locker and rear e-locker both engaged and disengaged. The rear locker really kills the turning radius.

Yeah sure. He obviously takes two different lines around that corner.

We take tight trails and turns all the time, and it's not the Detroit in the rear that pushes us straight. When the front e-locker is engaged, it's much harder to turn, and the vehicle wants to go straight. That's when I feel it.

I find no detriment to the Detroit in the rear, at least in my experience. I've never know a rear auto locker to affect turning radius, In fact, that's the first I've ever heard of that. Not saying it's wrong, but I've never heard that. Of course, no one's ever called me a rocket scientist, either, so there's that!

With that being said, everyone has what they like, and what works for them. Lockers are not a one size fits all. Depends on what your rig is for, and what you're wheeling in. Good luck on the build. Looking forward to see some posts of the project.

 

[XJ_ranger]

Another fan of front locked, rear selectable or limited for the tally.

Also consider some steering upgrades, hydro assist would be a popular choice. the front locked adds to the effort required to change tire direction with the steering wheel, but then pulls the front of the jeep around wherever they are pointed.

My buggy has a Detroit front and a Zip rear, and I don't have a desire to change that when I add rear steer.

My daily 97 xj has a lunchbox rear and open front, but that's because I cheaply needed a locker, and didn't want to spend the $ on gears/ shafts at the same time for the front end. being cheap drove me to choose to lock the rear, not overall performance.

I can feel the push from the locked rear for sure in 2wd parking in my driveway, as well as on the trail when compared to the buggy.

Just my opinions.

 

[Evan03]

I also love the front grizzly locker. If i had to choose id lock the front then run it with the rear open.

 

[dell30rb]

Another fan of front locked, rear selectable or limited for the tally.

Also consider some steering upgrades, hydro assist would be a popular choice. the front locked adds to the effort required to change tire direction with the steering wheel, but then pulls the front of the jeep around wherever they are pointed.

For steering no plans on hydro assist at the moment. Stock steering gear box, I do have a Barnes steering box brace and added a power steering cooler, also planning to do the WJ steering pump mod. I got a high steer knuckle for the D44

 

[Evan03]

For what its worth ive spent time on the trail riding with a buddy who has a hydro assisted rig. 1ton drag link over the knuckle.
Compared to my wj over the knuckle its pretty unimpressive. Many situations where hesunable to steer where i feel my wj with its better steering angles would still steer. And on the stock pump from 1989

Ive been trying to talk him into wj knuckles and redo track bar.