When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I don't believe there is any benefit to the older system. There shouldn't ever be a time where one front wheel needs 100% of the power. Also you have to realize that the trash control system is constantly using torque vector by Braking. The locking diffs are just a small part of the entire system. And there is at least a two to three mile per gallon increase with the newer system. For an example with the four cylinder, it is pretty substantial.
I don't believe there is any benefit to the older system. There shouldn't ever be a time where one front wheel needs 100% of the power. Also you have to realize that the trash control system is constantly using torque vector by Braking. The locking diffs are just a small part of the entire system. And there is at least a two to three mile per gallon increase with the newer system. For an example with the four cylinder, it is pretty substantial.
Is there any documentation on the LR website about the new system?
The increased mpg would be nice - is there a reason why it is not talked about more? The LR website still says 18/21/19 for the 4cyl which I believe is the same as advertised in prior years.
My unmodified (except 265/70/18 BFG KO2s) '24 p300 is getting 15.8 mpg in its first 1,500 miles. One would think if it made that kind of difference the advertised mpg would be increased to boost sales but this is all really interesting.
My unmodified (except 265/70/18 BFG KO2s) '24 p300 is getting 15.8 mpg in its first 1,500 miles. One would think if it made that kind of difference the advertised mpg would be increased to boost sales but this is all really interesting.
As a reference point, I have an MY21 D250 MHEV and I get 30 mpg on the freeway when unloaded (~2.7T), 24 mpg on the freeway when loaded at 3T, and about 19 mpg when loaded and pulling a 2T camper, and a full rack with surfboards, marquis etc. Normal range is between 435 - 500 miles per tank.
I have the expedition rack, a 270 awning, shower awning, bullbar, winch, tuffant sliders, ladder with baseplate for rotomount water containers, surfboard mounts, bravo snorkel... which all adds to the base weight and wind resistance.
Yes, it looks to be accross the entire range. The D300 (diesel non US) seems to have had the permanent rear wheel drive system since the beginning of production. The rest have all had the center differential until 23.5
The center differential system which is in all of the US production vehicles until model year 23 (p400) and 23.5 ( p300, p400 ) is set up like this. Power comes from the transmission and enters the transfer case. There it goes into a differential that can be variably locked by the traction control system. So for example, when no locking is applied, the differential puts power 50/50 to the front and rear driveshafts as long as there is no slippage or loss of traction just like any open front or rear differential. If you lift a wheel or slip im mud, just the slipping wheel spins and the other doesn't turn. Path of least resistance. So driving down the highway, the vehicle is in an all wheel drive state with the center differential mainly not locked and power is split to all wheels. The center differential is what allows the driveshafts to turn at different speeds when turning the vehicle to prevent binding since wheels turn at different speeds when rounding a corner. In a situation where 1 axle breaks or cv joint. The broken part has the least resistance and it will only turn. And you can not move. You can sort of move but the computer keeps unlocking the front and center diffs , so you just barely move when going straight. But turns are almost impossible. The center differential uses clutches to variably apply friction to the differential to prevent slipping when needed in turn locking it . The rear factory locking differential behaves very similar.
The 23.5 and up system works like this. Power comes from the transmission into the transfer case and is permanently connected to the rear driveshaft. There is no differential in the transfer case. It is what they call permanent rear wheel drive. The tcsse has a torque on demand unit that puts power to the front driveshaft when needed. It uses a similar clutched unit to do this, but the vehicle will always have power to the rear no matter what. Not the case with the earlier unit. Another difference is that the permanent rear wheel drive system has a front axle disconnect built into the front axle tube. At highway speeds the system will actually completely disconnect the front axle. These systems have a much better MPG because of this. I have actually driven one of these without a front driveshaft installed! You can not do that with the previous system. So as i stated in my post previously, if you have this system with our Sarek selectable rear air locker, you can still drive even if you break any one of the axles or CVs . With the factory rear locking diff you can break a front, but not a rear.
I believe the later system has many benefits. I really wish i had this system vs the center diff system that i have. I have broken an axle and it is not a good day. I always want to be able to try to drive off the trail even in 2 wheel or 1 wheel drive vs becoming a major burden on my friends trying to drag me off the trails.
Also, because of the axle disconnect, both front axles are the same part number, so u only need one spare for the front. Also much easier to replace the right axle from the previous system. The MPG gain is also a nice bonus.
Hi, Sarek.
I wend to my local JLR dealer (in Canada) and asking one of the sales guy if there is any information on new transfer case for 2024 model and he seems having no knowledge of this. Just like others, I googled a bit and did not find any information on this changing of transfer case. Just can't help scratching my head.
I am about to order my own defender and I would like to know what I will get.
Also, because of the axle disconnect, both front axles are the same part number, so u only need one spare for the front.
Well that's good to know! I'm sick of carrying two axles around everywhere I go, as I'm sure most of us are. If I get a 2024 I'll have room to carry one axle, a transfer case, and a pair of diffs, or can I get away with just carrying one and use it either front or rear?
Is there any way these diffs can be manually controlled?
As a Rubicon owner for a decade now and a fairly hard-core rock crawler, I am delighted to let the computer think about this. Engaging front and rear diff-locks, easing up onto slickrock, then, because you're on what is essentially pavement, feeling all the scrubbing and binding of two locked diffs, or remembering to unlock, and then relock when you need it, vs. the computer handling it all seamlessly... seems a big advantage in the rocks to me.
As a Rubicon owner for a decade now and a fairly hard-core rock crawler, I am delighted to let the computer think about this. Engaging front and rear diff-locks, easing up onto slickrock, then, because you're on what is essentially pavement, feeling all the scrubbing and binding of two locked diffs, or remembering to unlock, and then relock when you need it, vs. the computer handling it all seamlessly... seems a big advantage in the rocks to me.
Pictures of your ****** always make me smile. (TWSS) I'd say the drive back from there was nervy with the spare off the bead.
Pictures of your ****** always make me smile. (TWSS) I'd say the drive back from there was nervy with the spare off the bead.
Good eye! Thankfully it wasn't blown -- I was just running at 6 pounds, I believe, and rolled it off the rim on a steep side-slope. So I juiced the other four up to 10 or 12 pounds and didn't have much worry after that. It's all but impossible to flat those super swamper bias-plies.
And for clarity's sake, yes, it started life as a ****** Wheeler Edition, and I proudly leave those stickers on it. But since there are no lockers available on the WWE, I just used "Rubicon" as shorthand for "****** with lots of mechanical upgrades."
It makes me smile a lot too! Here's another to enjoy; stuck in the second waterfall of The Escalator element on Hell's Revenge trail. Pretzelled the Smittybilt 9500 winch trying to pull myself out, and after 40 minutes a couple guys in very nice TJs drove the bypass up to the top and gently pulled me out with a ****** line.
The upside was, I put a Warn Zeon 10S on the next day and have never regretted it. The Smitty was fine for winching, but their mounting hardware was crap.
Glad you people are doing so well and having all the funs
I am still trying to understand how to tell / check out what's the transfer case in a 24MY Defender.
OK, I will continue, typing as I am thinking:
if the center diff is a regular diff (open / lockable), then, when it is "Open", power from engine will go to the one wheel which is "hanging in the air". When engine is off, if we make one front wheel and one rear wheel in the air, then turning one by hand, the other one should turn, due to all three diffs are all open.
if the transfer case has no regular diff, and engine power goes to the rear permanently, then, with engine off and only one rear wheel in the air, it could not be turned by hand, due to the other rear wheel is sitting on the ground and rear drive shaft is locked, via transfer case and transmission, by the engine. Mean while, one can turn the front one in the air, because front diff is not connected to the center diff.
Just a mind experiment. I wish I had access to a MY24 and a MY22, so I could try it out.
01-30-2024, 09:14 AM
