Is selec track (or full time 4WD) inherently bad or weaker?

[Savage1]

Hey guys,
Great board you have here. It’s nice to see people be able to disagree and still act like adults.
So, total rookie here but I think I’m getting close to pulling the trigger. I’ve narrowed it down to a Mojave or Rubicon. Still not sure if I’m going new or a damn close used one. From the start I had the full time 4WD in my head as being one of the options I had to have. Just made sense to me if you’re anywhere that gets snow. (In my uninformed mind).
I’ve looked at hundreds of vehicles online new and used and have literally seen it on probably 5 or less.
With it being such a cheap option why do people stay away from it?

Sponsored

 

[NachoRuby]

I'd get it if it were available on my transmission choice. But also, it's a fairly new-ish option on these, so it hasn't caught on yet. I think a better usage case than snow is honestly rain. In snow, since you can shift into 4wd while moving quite easily, I just shift back and forth between 2HI and 4Hi as conditions require. Or if it's really nasty, I leave it in 4HI. In snow, it's more of a very nice luxury than a requirement. I still wish I had it, though. But I'm entirely unwilling to give up my 6 speed. The old school part time 4wd transfer case is still very good for snowy weather. Exactly as good, in fact, once 4wd is engaged on both.

 

[07052021]

I don't believe the Selec–Trac Full Time 4WD became available to order until the 2021 model year. I also don't think it's a common option for a dealer to add to a Gladiator they'll have sitting on their lot. You'd probably need to submit a factory order built the way you want or find a Glad that was built for someone who wanted full time 4WD.

With that, buying used right now will cost you a lotttt. If you can wait 10-16 weeks, do a factory order through one of the forum dealers (5-7% below invoice pricing).

 

[JTBurns]

It wasn't always an option, so that's why you're not seeing it on used rigs. New? Not sure why dealers don't add them to their specs, but no reason to avoid it. The truck is still RWD just has a 4 auto selection on the transfer case

 

[dcmdon]

Its a no-brainer in my opinion. I just drove my new Gladiator back from TN to MA. Along the way I hit several snow squalls.

This includes one in WV where the highways were 100% unsalted and un plowed. AWD is a huge help here.

I drove about half the trip with it engaged. If the road was dry I left it off. Around town its on 100%. On the highway I will turn it off on a dry road just to try to eke out an extra 0.5 mpg. (if its even that)

For $600 its a no brainer.

 

[Trailman]

Someone @jsalbre gave an excellent description of the difference in reply to one of my posts awhile back. In short, no reason to avoid them, and they would inadvertently fix one of my annoyances with the Gladiator.

But, in terms of snow, as others have said it is super easy to go in and out of 4HI. I actually enjoy it since it gives me some manual, tactile experience in a truck with an automatic.

4 Auto does not switch into and out of low range. However, having it on his JT would eliminate the feeling he's talking about, for reasons that will be clear in a moment.


OP:

The vibration you're feeling, commonly known as "crow-hop" isn't due to any binding so much as just the nature of the u-joints used in your front axle. Because of how u-joints are constructed the output shaft is continuously changing speeds versus the input shaft when the joint isn't straight, so each rotation your tires are speeding up and slowing down. How much of a change in speed there is is dictated by how far the wheels are turned. It's made worse by the fact that your two front wheels are rotating at different speeds from each other. See the "Equation of Motion" section of this Wikipedia article for more info: https://en.wikipedia.org/wiki/Universal_joint.

Now, if you had the 4 Auto transfer case (MP3022) in your JT it would have been built with constant velocity (CV) joints in the front axles. CV joints don't suffer from he variation in input vs output speeds that u-joints do. We've known of this problem, and solution since the 1600s. The downside with CV joints is that if they aren't taken care of very well any contamination can destroy them in short order.

The reason the MP3022 is specced with CV joints is because it's theoretically more susceptible to damage from the vibration of u-joints.

There are some high-end CV joint axles available from RCV Performance for Jeeps and other 4WD vehicles.

 

[NachoRuby]

Its a no-brainer in my opinion. I just drove my new Gladiator back from TN to MA. Along the way I hit several snow squalls.

This includes one in WV where the highways were 100% unsalted and un plowed. AWD is a huge help here.

I drove about half the trip with it engaged. If the road was dry I left it off. Around town its on 100%. On the highway I will turn it off on a dry road just to try to eke out an extra 0.5 mpg. (if its even that)

For $600 its a no brainer.

Real question, not to be argumentative, but what's the difference between shifting 4h auto on and off for mpg as you described, and switching between 2HI and 4Hi for those of us without this option? You're still moving the lever. Imo, the best usage case would be for those times when you want to just leave it on without futzing with the T-Case lever. Those without 4hi auto would still switch to 2wd once on the plowed highway, and get the same mpg gains for doing so.

 

[FrankFrqnkFrank]

I agree on the comments about 4WH in snow, but when someone in my family (who doesn’t understand how 4WD could affect handling on dry pavement) is driving my JT in intermittent inclement weather, I’m glad I can know they are using the AWD function

 

[Mac]

Its a no-brainer in my opinion. I just drove my new Gladiator back from TN to MA. Along the way I hit several snow squalls.

This includes one in WV where the highways were 100% unsalted and un plowed. AWD is a huge help here.

I drove about half the trip with it engaged. If the road was dry I left it off. Around town its on 100%. On the highway I will turn it off on a dry road just to try to eke out an extra 0.5 mpg. (if its even that)

For $600 its a no brainer.

Is there any dash light or indication when in awd that it has locked in the front axle?

 

[Labswine]

GET IT!!!! You won't be disappointed especially when driving through snow on regular roads and highways. I had it in my '96 and '03 Grand Cherokees and when it got messy, that 4PT was AWESOME!!! Plus, unlike AWD (which is always there) you can simply put it into 2H and not be pushing that extra drive train. I did have the Quadradrive II in my '02 4.7L, '08 Hemi, and '11 Hemi Grand Cherokees. There wasn't any real detriment to fuel economy except that even though my '11 had the same Hemi as my '08, the '11 was a pig on gas (16 hwy when I was getting 21 hwy with my '08). I wish the Selec-trac was available when I ordered my Gladiator Overland back in May of '19.

 

[NC_Overland]

Yeah, it wasn’t available when I got mine. I probably would have gotten it since I was used to it on my 2017 Canyon All Terrain. However, I’ve found that it performs surprisingly well in 2wd and I don’t feel the need for it.

 

[jac04]

Is there any dash light or indication when in awd that it has locked in the front axle?

Yes. When you shift into 4Auto, the x-fer case postion indicator light will blink until everything comes up to speed and the FAD locks the RH axle shaft. Then the light will go solid.

 

[saintpauljeff]

I traded my MY2020 for a MY2021 JTR specifically to get this feature (along with LED lighting); I did find (1!) apart of dealer stock on the lot in the 2 months I was actively looking for Rubicons/Mojaves, actually identified this one as it was in transit, and when it landed at the dealer I worked fast to get a deal done

Agree with the others, it's a great option to must-have if you live in inclemate winter weather; I used it 3 times the first week I owned the truck as many roads up here go from (crappily) plowed snow to bare pavement and back to snow again.

 

[Suszynch]

the full-time systems are pretty well refined IMO from other vehicles in their lineup that uses the technology.
There are more pieces involved, and probably electronics to match than its standard counterpart. I'd imagine for 90% of what people want from a jeep it will work just fine. Having more pieces, with aging ownership you could expect higher repair costs if you ever had an issue.
id imagine most people will prefer a system that doesn't have the 4wd 'bucking' when turning, no idea of the affliction it has on fuel economy though.

 

[Mac]

Yes. When you shift into 4Auto, the x-fer case postion indicator light will blink until everything comes up to speed and the FAD locks the RH axle shaft. Then the light will go solid.

Thanks, but it is still in rwd at that point, I was wondering if it indicates anything when the front axle is engaged from the transfer case when it detects slip

Sponsored