Zed

52 minutes ago, Josh S said:

Yes, I am aware the Rubicon is not suitable for four low which I mentioned earlier, so perhaps I should be changing my car or changing my transfer case as I am struggling to see this is a technique issue since it is related to RPM and torque. This of course contradicts all that has been previously said on this thread about for low being unnecessary, even at an expert level.
 

I dont think that's a fair conclusion tho... you're asking in a Carnity Forum but applying it elsewhere. Carnity Intermediate is not the same as other club's intermediate or experts. So what works here may not apply elsewhere, and it all depends on the car. Granted, you're asking for Jeep Wrangler, but when you're leading a drive, you get a sense of what works for the whole convoy, and the Seniors of Carnity have given that input by suggesting 4Hi. This I concur, all my 100 drives with Carnity I don't see a need to go 4Lo except to self-recover.

Once when driving with friends outside this club, we did notice my friend's Jimny was struggling in certain climbs we're doing, so I asked his permission to try out his car and him in passenger chair. After various trials we find that the Jimny performs well in climbing with 4Lo instead of 4Hi, and his Jimny was a manual.... thus we have a combo where some ppl drove in 4Hi and some had to go 4Lo, whatever works for that individual driver...

So all these 4Lo vs 4Hi just depend on the car and the kind of drives, no one formula for all kinds of drives and for all clubs everywhere...

Jimny changing to 4Lo to get out of bowl

2 hours ago, Josh S said:

9 months and 40 drives into the world of off-roading (and without doubt, the best hobby I’ve ever had) I thought compelled to bring the thread back from the dead with a few additional thoughts and questions!!

I have recently been driving with some experienced convoys in Sweihan. It’s a different kettle of fish compared to the drives in Sharjah and has a lot of switching, higher speed crests and larger climbs. Everyone drives in 4L other than me as my Rubicon doesn’t allow for it  

When it comes to reaching the crest, and either riding it or switching, we tend to be travelling around 40-50km/hr which is right on the red line of 1st. It’s important to keep high RPM here but being so close to red line means there’s little room to blip the throttle if I need to. Meanwhile, if using 2nd gear at the same speed, the RPM is much lower and the torque feels substantially less than I am used to in first, and does not feel like enough, especially if the speed drops a little or the sound is very hot and slippery. As such, neither 1st or 2nd feels right. (Note, I have chosen to drive manual as I find it more enjoyable and engaging than auto).

So my question is, would this be an example where 4L would provide more control leading up to, and on the crest, as the gears are shorter and I’d have much more torque to play with at the same speed, or is this down to wrong technique? I find myself thinking it’s a 4H issue as nobody else in the convoy appears to struggle with the RPM/Torque and they are all in 4L  

 

@Josh S i think this has been answered before, I hope you're reading this and not skipping it  

1. If any of your experienced friend or marshal in J.N. has Rubicon, they will have already swapped their transfer case from 4:1 ratio to the JL 2.7 ratio so they can drive Rubicon in 4Lo. Refer to table at end of post below. The higher the number, the higher the torque BUT less speed.  The lesser the number the lower the torque but more speed. As mentioned in previous post, Santoso has changed his Rubicon transfer case, and though you see him as 50 drives only, he's a Senior (1 level below Marshal) in UAEO***.   Complete Table of Calculated Drive Ratios between Rubicon 4:1 and JL 2.7 is at the end of this post, cos I have other solutions too and didn't want you to skip the maths  

2. Another option: Grind your camshaft so it will change your torque & speed profile at higher rpm. This would increase your rev limit so driving 5000rpm feels like factory 3500rpm.

3. Another option: talk to a tuner and see if they can program the computer differently. Am not familiar with the Pentastar engine, but let's say if any of the ratio is hardcoded somewhere, you can change the constant of 4 multiplier to 2.7 multiplier electronically without mechanically changing stuff.

4. Stay incumbent in status quo: clubs like J.N. would put you last before sweeper so as not to slow down the experienced drivers in front  

TABLE of JL 2.7:1 Transfer Case vs Rubicon 4:1 Transfer Case

Now because 4Lo is a gear reduction system, basically driving in 4Lo reduces your max speed, and the reduction is done via the 4Lo ratio, Rubicon Max Speed of 50km/h in 4Lo is due to Max Speed in 4Hi divide by 4:

And here's a complete table of calculated drive ratios.

• Yellow means when Rubicon is driving 4Hi 1st Gear, it's equivalent to JL 4Lo 3rd Gear >> this is why JL peeps drive in 4Lo cos they have more "variations" before they hit cruising speed at 4Lo 8th Gear. 
• Rubicon ideal sand gear is 4Lo 6th gear, but due to gear reduction max speed is limited to 50km/h. Only way to drive faster in 4Lo is to change transfer case to JL version.

Cheers,

Z.

32 minutes ago, Luke K P said:

Given your descriptions above.. think maybe the 'sand mode' ( 4H + diff lock ) is aimed at american baja type flat sand desert driving rather than up and over of dunes.... ie lots of drifting on fairly level ground.

@Luke K P @Julien Recan check out this recent Dakkar Rally "amazing shot" video, the car is "fighting gravity" on a side-slope.  Center Diff Lock + Rear Diff Locks will help here:

• Center Diff Lock will ensure both front axle + rear axle spins at same speed. 50-50, not 40:60, not 30:70. 50:50 means better traction because if your rear tires are slipping, front tires still have 50% power to pull (assuming the sand allows it).
• Rear Diff Lock will ensure rear-left + rear-right tires are always spinning. What if you hit a small stone and your rear-left tire is in the air? Without rear-diff-lock, this tire in the air will spin and the tire on the ground will stop spinning (at least momentarily until all tires land on the sand again). BUT this driver has to go down in a controlled manner and not full 90-degrees down.

4 minutes ago, RiadJL said:

Interesting..

I haven't been able to climb up Iftar bowl's center face so far. My impression was the wheels spend too much time in the air because of all the tire tracks in the sand there and so I'm not able to put down enough power. Do you think diff locks would help in this case? or sway bar disconnect?  

hi @RiadJL each scenario is different, tag me if you're joining next Iftar Bowl drive and will be happy to check your various configuration. But please go through these first before jumping to diff lock:

1. Lower your psi. I had trouble climbing some parts of Lady Dune, but was able to climb after deflating all tires to 10 psi. Of course if you don't have thick sidewalls, safest is to stick to 12 psi (now you have a reason to get taller tires that have "70" or "75" in the middle like 265/70/17)

2. Try in 4Lo but higher gears (e.g.  4Lo + 3rd gear or 4Lo + 4th gear). This will give you lots of torque but also some speed.

3. If you're tires are jumping in the air and the terrain is bumpy, you need firmer shocks (which is perfect for offroad and bumps but too stiff for daily driving).

4. If 1+2+3 above are done but still "no power", you can try Center Diff Lock only

5. If 1+2+3+4 above are done and still "no power", allow me to drive your car.

6. If 1-5 are done and still "no power", let's discuss buying another car  

@Luke K P @Julien Recan  please read my prev article on this if you haven't >> https://carnity.com/forums/topic/16736-diff-lock-simplified-center-rear-front-explained/

The Standard Order is Central Diff Lock > Rear Diff Lock >> and last Front Diff Lock.

Am sure there's a very technical reason for this, one involving blowing out diffs, but for shortcut let's just say this is how it's done in Mercedes G-Wagon and Toyota Land Cruiser 80, so let's follow Mercedes & Toyota engineers regarding this order of pressing the buttons  

Here's my take on your new orange Ford:

1. First check if your Center + Rear Diff Locks are automatically engaged when you switch to 4Lo. My Nissan Y62 Patrol did this, everytime I turned 4Lo, it automatically enganges Rear Diff Lock (thus also Center Diff Lock). My Jeep Grand Cherokee doesn't do this, so if I go 4Lo, it doesn't engage any diff locks.

How to test? You can't test on sand. In your parking space, turn on 4Lo then move forward 3 steps so it fully engages 4Lo. Then turn your steering wheel full-left (or full-right) and accelerate. If your tires are slipping or you hear screeching sound, means your rear diff is locked. Remember the purpose of Differential is so that left tyre and right tyre can spin at different speeds (which is needed for turning full-left/full-right mechanism)

2. If #1 doesn't make any sound means you are in 4Lo but in open diffs mode (no center and no rear diffs locked). Great, you can drive in 4Lo at high-speed to get more torque. 

3. Why would you ever want to drive with diff locks engaged at high speed ??? Read Point #1 above, the purpose of having differential is to allow left-tyre to spin faster/slower than right-tyre, which is needed for full-turn.

Yes in low-traction platform like soft sand and water, the tires still slip but they will not screech and make sound like in your concrete car parking or highway asphalt. But still, do you want to risk it? Example: you're riding on a ridge with soft sand with Center + Rear Diffs locked, then suddenly you have to make 90-degrees left-turn to exit the ridge riding. If the sand is hard (due to rain), now you're turning on a non low-traction platform. The tires will slip to make the turn, but because you're no longer in soft sand, you will be turning like a Rally Driver, with that drifting effect, which is fine on horizontal levelled plain areas (sabkhas), but on a ridge? Only the braves will risk it....

I've asked some "crazy" drivers why they turn-on Center Diff Lock when driving, and these are their reasons:

3.1.They want to drive in a STRAIGHT LINE very fast. Rally drivers do this. You can also try when you're climbing up in a straight line, but not when you're going up then decided to make a loop.

3.2 They want to drift when they're side-sloping, only doable with beadlocks. I've seen this in front of my eyes: so the car looks like fighting gravity, but in fact they are SLIDING horizontally with the nose facing 45-degrees up. Very cool for videos, but even I don't want to try that 😂

PS: we can do a 30-mins "testing session" after an official drive to test the various modes of your mighty Raptor 😁

@Luke K P @Ishak  see you on the 101 th drive next time pals 👋🏻 🙂 i'm guessing @Frederic's exit point will be Nahel so who knows we might cross path tomorrow 😁

7 hours ago, DP1011 said:

Unless the donuts and shawarma are from last week's drive😂! 

how did "shwarma" get inserted into this request? If @Ishak & @DP1011 crave shwarma, we'll have to extend the drive from Nahel to Al Ain airport so lunch will be with shwarma 😂

1 hour ago, Luke K P said:

@Zed come do drive 100 out here with us this weekend mate 😎

decision...decision 😅  this drive is already full, while the other drive starts at 7am and less full 😁 will toss a coin 48hrs before 🪙

39 minutes ago, Gary F said:

Maybe we will find a moment for that experiment @Mark B @Zed

 

@JeromeFJ front right sway bar link extra tight in preparation 

@JeromeFJ's entry point is Ramlah Sweihan Bowls Bowls Bowls Strip... it will be a good area to test 4Lo vs 4Hi ... also I just installed Mopar original beadlock wheels for the Cherokee (got them for free so can't refuse installing them  ) - I might try climbing in 4Lo with 6 psi 😅

20 hours ago, Gaurav said:

Reviving this out of genuine curiosity.

Has any of Wrangler owner ditched BF Goodrich and switched to lighter AT tires like Geolandars or LTX force?

• BFG weighs 30 - 35 kgs
• Geolanders: 18 kgs
• LTX Force: 19 kgs

If anyone has done that, you might not need 4L for hill climb as bigger and heavier tires are counter-productive for sand dune - long hill climb.

Hi @Gaurav , Julius (the Red Wrangler in my DCT team) did that and sent me his comparison of tires table below. He switched to Cooper AT3 4S (19.5kg per tyre) 285/70/17 for 5 years and still drove in 4L. Recently before DCT he switched to Geolandar P-rated (20.4 kg) 285/70/17 and again still drove in 4L. Told me the reason was "more controlled" but I'm also guessing habits don't change easy    With @Naveen Raj confirming he drove in 4H 2nd gear, this confirms both 4L and 4H can climb Nagra (last minutes in https://www.instagram.com/reel/Cy5P6SaJU9s/ ) , so it doesn't matter 4Lo or 4Hi as long as you're confident you can make it  

6 minutes ago, Jaro Tuzinsky said:

They will drive crazy for this hunting:( it will be dangerous or?

Can't comment on that in public forum, I'll just tell you tomorrow in the briefing  

7 minutes ago, Jaro Tuzinsky said:

Is it the treasure hunt with UAE off-roaders?:( i heard about it but didn’t know where it will be.

yes it is, they just announced today, was hoping they will be in quiet Razeen 😂 but guess we'll see tomorrow how it'll be 🤞🏻

Hi Marshal @JeromeFJ  heads-up there will be around 150 cars in GPS coord 24.394510, 55.483620  at 7am tomorrow for a GPS Treasure Hunt briefing, after that those cars will randomly go around to pick up flags until 3pm...   Sweihan is still a big playground, but I think towards Al Ain airport will be less crowded  

cc @Gary F  good time to check 4Lo vs 4Hi ? 😁  will be joining w/ my Jeep WK on this drive...

2 hours ago, Gary F said:

 Great post @Zed been thinking about this a lot recently and with 50 drives I think it’s time for some experimentation.

Driving the Jeep Gladiator Sandrunner (Mojave in USA) its already packing a few hundred kilos of extra weight vs a Wrangler between the bed, reinforced frame and larger axles.  
 

I often find on larger climbs in 4hi I’m running out of RPM in first and torque in second, with 31 inch tires.
 

The Mojave has a 2.71:1 transfer case allowing up to 70kmh speeds (50mph)

might be time to find tall dune for some experiments. 

Congrats on reaching 50 drives @Gary F and your willingness to experiment to find your own driving style 👍🏻 . Please document it like this https://www.instagram.com/reel/C2SVhe5JgRU/?igsh=azVsa3B2c3VnZmN6 (middle of video he revealed it's 4Lo 3rd gear). Science says an experiment that can be repeated by others using the same tools means your paper is accepted by peer reviews and you've proven your point 😅

Pro Tip: start from 4Lo 3rd gear. ZF Transmission Triptronic is awesome that it will automatically cycle 1st & 2nd for you and hold in 3rd. Most Torque Curve diagrams say 3000-3500rpm is engine's peak torque, so when climbing, you want to find the best gear that's in that range and not go above 5000rpm (contrary to most beliefs, at 5000rpm you're actually losing torque).

Once you're in flatter areas, upshift to 4Lo 4th or above to keep rpm in the 2000-2500 rpm range to save petrol, and cool both engine & transmission. Downshift again before climbing. And when you're stuck, you're already in 4Lo so you can just shift to 1st or 2nd and do the blip-blip 🙂

*Also call me if you're going to choose Sweihan, Faya or Khatim for testing grounds, be happy to join if not busy ✌🏻

39 minutes ago, Harshal said:

Not sure about Jeeps specifically but my Tundra has relatively heavy tires (315 Baja Champions), of course its Supercharged and modified a lot, but I still never use 4LO, (if you really want better response from heavy and large tires, it better to regear) it stresses the car out too much and I only use it if the car is really badly stuck. In general for most cars, use 4H, use 4LO only if you see the car isn't responding well or when you feel that it needs that extra push.

To cut the story short: Senior Marshal Fadi drives in 4Lo, and his convoy won the Desert Champions Trophy (I believe all in his convoy does the same; driving in 4Lo). That's 6 hours of non-stop driving in 4Lo and so yes you can get away with it.  His opinion on 4Lo here >> https://www.instagram.com/reel/Cm6VAp4q6lR/?igsh=ZnozYXVhbTNhZHNv

So I've re-geared 4x already and I've seen what's inside my transfer case + front & rear diffs. I would never drive 4Lo high speed in my Gear-Driven Transfer Case Land Cruiser, but I've driven a few times in 4Lo with my 5-speed Jeep with Chain-Driven Transfer Case... because Gear-Driven Transfer Case is only suitable for low-speed driving.  This is why there is No Generic Rule to 4LO: it primarily depends on the car and secondarily depends on the driver if he wishes to experiment with his car  

1) First front & rear to 4.88 gearing to cater for heavier tires on the Land Cruiser

2) Second opened my Transfer Case and re-geared the 4Lo gears to make 1:3 reduction in 4Lo only.

3) Third when installing ARB air lockers (carriers) I opened the front & rear differentials and notice the ring pattern signify that my differentials were not properly installed the first time. So I re-geared front & diff again, this time making sure proper break-in process is followed and triple-checking the backlash & preload of rings & pinions.

4) Finally I opened my Transfer Case again cos I was afraid same thing might happen to the Transfer Case as with the diffs. Then for fun & experiment I re-geared the 4Hi gearing in transfer case by simply changing 2 gears. This basically makes my 4Hi "spin more".

The 4.88 in front & rear diffs + the 10% underdrive in 4H gears Transfer Case = 5.3 final drive ratio so I don't need 4Lo for normal sand driving (even if my Transfer Case was Chain-Driven).

The whole Transfer Case system is just a GEAR REDUCTION mechanical device. And so a 1:4 Transfer Case Ratio for Rubicon just means the max speed in 4Lo is  1/4th of the max speed in 4Hi.  It's like driving slower than 1st Gear, but because there is no -1, -2, -3, -4  Shifter, the wizards invented Transfer Case to go Lower than Normal 1st Gear. Obviously there is no use of these lower gears in the asphalt / normal highway, but depending on car (should you wish to experiment), it may has some advantage in loose-traction areas like sand and slower-but-precision drives like rock-crawling.

So will 4Lo break your car? Judging by the simplicity of Gear Reduction concept, it probably won't. BUT older cars like my Land Cruiser have Gear-Driven Transfer Case whcih are not suitable for high-speed motion, so I agree with @Carnity Marshals here that you shouldn't drive in 4Lo with these kind of cars.  Newer cars with more transmission shifts and Chain-Driven Transfer Case have more flexibility... with the Chain TransferCase you can drive faster than with Noisy Gear-Driven TransferCase.  Most people who broke their transfer case in 4Lo most probably broke their Chain in the transfer case too, but for the adventurous who like to experiment with their cars, go ahead and drive in 4Lo... the theory has been laid out, and now it's time for practice 😁

Congrats @JeromeFJ 👏🏻 funny thing i always thought you were Marshal already 😄 Amazing how far you've gone with that Stock FJ 👍🏻, looking forward to driving with you again this season...

was enjoying this debate while eating popcorn, and I thought when the Crews started giving their advice, this thread would have been finalized, but nooooo 😂

@Josh S the easy answer is if you're driving with Carnity Marshals, 99% you'll drive in 4H. 

Using @Looper's video here >> https://www.instagram.com/p/Cz1suDgNlgq/  you can see the speed stats and he's driving around 50 km / h. Your 2021 Rubicon has the 4:1 Transfer Case Ratio ... Then the max speed is a quarter (1/4) of the max speed in 4H, assuming 160 km/h max in 4H, your 4L max speed is 40 km/h. Any more than that and you're redlining, overheating both your engine and possibly reducing transmission life.

Now those other JL Sports have 2.7:1 Transfer Case Ratio, so in 4Lo their max speed is 1/2.7 which is 60 km/h. If they're following Looper in that video, they can drive in 4L and get away with it (although I'd postulate they can't drive too long without breaks).

Yes you can run 55 mph (100 km/h) in 4Lo like video below >> https://www.youtube.com/watch?v=iEboJi5FhpE   Look how "Torquey" the car is when in 4Low.

The Marshals who drive in 4Lo usually have these characteristics:

1. They firmly believe the Owner's Manual only applies to Asphalt Traction. When they're driving in very loose traction like super soft sand, 4Low has more tolerances thus you can go higher than the manual says.

2. They have BeadLock Wheels, which are heavier and need more torque to turn than normal lighter stock wheels.

3. They have Heavier Tires, combined with BeadLock most probably 285s (33") or taller. Again, more torque needed to spin the tires.

4. They have 6-speed or 8-speed transmissions, so they can get away with 4Low + 8th Gear which is close to 4High + 1st Gear but more torque.

5. No Carnity Marshals have #1-3 above, so back to original quick rule: when driving with Carnity, use 4High  

@Mohit Gurnani that FJ stock is just waiting for the owner to unleash the sleeping lion, more practice will wake it up mate 😊👍🏻 , btw straight before turning left >> https://www.instagram.com/stories/zeddyiskandar/3269732911185976346?utm_source=ig_story_item_share&igsh=MWIzNm40NzZ0ZTdieA==

2 minutes ago, munkybizness said:

@GauravSoni, I’ve just managed to lose my wallet this morning and I’m running about trying to hunt it down and deal with all the ID issues. Will have to bow out until I resolve this. Thanks so much for trying to accommodate me though 🙏🏽

hi Mayank hope you get it back soon with all the IDs and cards. Similarly while paying for coffee today I realized I lost my ATM/debit card. Blocking & getting new card was easy through app, but now I've to wait until after new year to get new card... means no spending this long weekend 😭

28 minutes ago, GauravSoni said:

@Zed @Imteeaz @munkybizness I will add you guys to the drive… let me know if you. Are up for it!!! Please confirm

Confirmed Captain 👍🏻

38 minutes ago, Gurcharan Mehta said:

coming from dubai, i see online the last gas station is around Jebel ali, is there any other gas station closer to the starting point, if so would appreciate the coordinates please, thanks

Adnoc Faya 891 is 10mins from meeting point:

ADNOC Service Station | Al Faya (891)
800 300
https://maps.app.goo.gl/d8v4yPK1uhCRRWNfA?g_st=ic

33 minutes ago, Gary F said:

Update is it’s gonna be in the shop a few days , wasn’t coolant, on actually putting it on the ramp it’s the classic Jeep pentastar 3.6 crankshaft seal leak, on a engine with only 33k ! @Srikumar

think it's a Jeep problem, I also have it on my Grand Cherokee Hemi WK and chose to ignore it by doing top-ups if the oil dipstick says so.,, it's good your car is still under warranty so you should get that job done for free, for the rest of us old car & out-of-warranties, the labor cost doesn't justify simple top-ups 😂

32 minutes ago, Looper said:

But I found that Carnity discipline is very strongly embedded in all of us. After the first few min, the short convoy spontaneously decided on a convoy order and followed it till the end without breaking it. Frankly, I was very proud of the culture of discipline we have at Carnity and the strong sense of safe driving etiquette that comes along with it.

Put me in 2nd Lead and that discipline will be tested 😂 *joking, i won't separate the convoy, most probably 50m left & right from marshal's footpath 😁

3 minutes ago, Srikumar said:

 

a mix of rolling dunes

please use "undulating", "wavy" or "reverberating"... i have phobia of the word "rolling" when it comes to this marshal 😂