Offroad advice/experience on mountain trails

[Deno Vikram]

 Hello Fellow Offroaders!

A brand spanking noob to the Offroad world with a 2016 Pajero LWB here with an age old question of 4H vs 4HLCvs 4Llc but in a different setting of rough rocky/gravel/loose gravel terrain with steep inclines.

My question to the Pajero experts/Gurus here is how best to tackle the steep mountain terrain with your 4x4, what Offroad and driving modes to be used? Also would love to hear you experiences on such adventures.

I had recently completed a trip to Jebel Hamri along with a fellow FJ cruiser and has come back with a lot more questions about the Pajero. The most important being the proper use of 4H/4Hlc/4llc on steep climbs with hard terrains and areas with loose gravels. I started the Jebel Hamri offroad trail in 4Hlc and had to change it to 4llc towards the end of the trail due to my first time experiencing the steep climbs The temperature warning sign on my dashboard lit up by the end of the trail.  This had me a bit worried and confused, I knew I had been pushing the pajero on the 4llc mode which caused the issue. Please share your expert advice when tackling such terrain.

I plan to visit other similar places such as Wadi Sal, Jebel khatt etc that may be a bigger challenge and I would like to be more prepared than before,  your experiences/advice will definitly point me in the right direction.

Thank you
Deno

 

[Frederic]

Hey @Deno Vikram ! Welcome to Carnity !

The difference between 4H and 4Hlc is simple:

- In 4H the power ratio between front and back will be around 30/70, and the viscous coupling in your transfer case will make this variable based on the torque needed. 4H is the most common used setting for offroading with your Pajero.

- In 4Hlc the power ratio becomes 50/50 and instead of the viscous coupling this becomes a fixed ratio.

You mentioned you have completed some mountain trails. Be aware in this summer this will mean your engine will run very hot, because the main issue is the fact you are driving really slowly so there is hardly any ram-air effect pushing fresh air through the radiator, and the fan itself has to do all the work.

On steep trails, definitely move to using 4L (low gearing) which will allow you to get good torque and steady climbing ability.

You mention your warning sign lit up: was it the engine high temperature or transmission high temperature ? While doing steep climbs the automatic gearbox will be hunting a lot (up and downshifting) which results in overheating transmission. This can be avoided by using your tiptronic (manually selecting 1st or 2nd gear). That way the transmission will stay in the same gear while you are climbing.

 

Some info below:

 

 

[Gaurav]

3 hours ago, Frederic said:

On steep trails, definitely move to using 4L (low gearing) which will allow you to get good torque and steady climbing ability.

Just to clarify, I totally agree with the above comment to use 4L on super steep climbs while keeping speed under 30-40 kmph max. Once done with the challenging steep climb, you should switch back to 4HLC for the rest of the mountain.

4L is your trump card and you should only use it when it's really needed. With an extended period of driving on 4L on sand or on the mountain, you will damage your transfer case soon.

[GauravSoni]

Hi @Deno Vikram welcome to the club!  The gods of the club have already spoken !!! Here are my 2 cents 
Always use tiptronic/ manual shifting of gears while doing steep / mountain climbs including the gravel/ loose tracks… 

I personally prefer 4hlc during these drives however switch to 4l during descents. Use engine braking on your way down which makes it a lot easier on your brakes and control over your car. 
I am also curious if u deflate your tyres as well.. it’s best to go down to 25 psi on such terrain to reduce stress on transmission as well as disengage traction control to prevent wheel spin on loose gravel.. 

[Gaurav]

8 hours ago, GauravSoni said:

The gods of the club have already spoken !!!

Nobody is god here, we just know a little bit more than others based on our failures and experiences.

And we still learning from actual Gods of off-roading on what works and what doesn't. Remember liwa extreme recovery last year that tested everything we know and so many things we don't know?

Thankfully we were blessed with amazing teamwork, that graced the whole experience.

[Deno Vikram]

Hey Guys! Thanks and musch appreciated for your response.

Based on your feedback, apart from the offroad modes Tiptronic is key to climbing steep hills on the Pajero, something that I have never used before. I will definitly give it a try next time.

In tiptronic does it stay revving in the same gear regardles of the rpm or does it auto move to the next gear when the rpm hits the limit for the particular gear?

Also please share your thought process on how do you judge which offroad mode to be in when tackling a steep climb. Experience is the key here but do you use any 'personal logic' to make the decision.

@Frederic Thank you, your post is very informative. It was the transmission high temparature warning light that lit up.

@Gaurav Yup I totally agree with your point on 4L, I think it was the execessive driving on 4L that had an impact on my transmission temparature. Never gonna do that again until I am absolutely sure I need them.

@GauravSoni Thanks for the advice on deflating the tyres, I had'nt deflated my tyres and the thought did hit me during the last sections of the climb but instead I just bulldozed my way through on 4L (somehow).

 

 

[Gaurav]

So now you know for sure that fully inflated tires are the actual root cause of the struggle and stressing the car unnecessarily in Low gear.

The ideal mountain deflation is 20 - 25 PSI. In general, 25 PSI is perfect for loose gravel and 20 PSI when that loose gravel turn to fine gravel and slips your tires on every turn. A slightly more deflated tire will hold the traction better in those instances.

However, if you go below 20 PSI then you risk getting tire cut with sharp rocks or angle, so always start with 25 PSI in HLC and work your way up in the mountain. In steeper climbs, when you feel that pressing too much throttle is not resulting in the same speed, then you can switch to LO gear for that struggling patch or incline and go back to HLC once done.

Also, LO gear is very good for coming downhill as Gaurav Soni mentioned, that takes a lot of load from your brakes and does not eat the brake pad after one descent. The only catch is to keep your speed lower than 40 kmph in Low gear and you will be fine.

[JamesBY]

Hi Deno! Good to see another solid mountain driving fan around. 

I wanted to highlight a couple of points outside/alongside what has been mentioned already:

1. Steep climbs should always be done in tiptronic and either locked in 1st or 2nd depending on the grade. Personally I like a very gentle climb in 1st, 4H (no lock) and just trundle up. This is effective when you're on a well maintained track that also has a lot of switchbacks. Important to note: Having it in any difflocking mode when you're on a switchback route will cause "hopping" as the locked differential will not allow differing tyre rotation speeds. It'll also really piss off your diff and can be dodgy if you're on a steep switchback descent (there's an interesting one in the Jebel Yibr area..steep enough that part of it is line-textured concrete as I believe it heads to another military installation)
2. Although we're all fans of the Pajero TC system, certain trails around the UAE have some differing terrain at a high incline with well developed hollows/dips. As mentioned by Gaurav, fine gravel mixed with sand on a compacted surface is probably the most irritating thing you can encounter if the route is poorly maintained/damaged/filled with hollows. In this situation, it is acceptable to get 4Llc going and to lock the rear differential to turn off the TC (dune riders will generally have a killswitch installed). In the majority of situations you don't want the TC to be off, partially because the Pajero system is highly effective, and partially because you might damage the trail further for people behind you in your convoy. However..when you've exhausted your options - Guide Assisting, 4Hlc, 4Llc, in that order specifically - it's time to get a bit more aggressive. At this point you need to make sure your guide is standing at a decent distance and ensure he/she is always uphill of you. Come at it with a little more speed (A LITTLE ONLY!) and when you think you're about to hit that hollow prepare yourself to give the pedal a little more pressure as soon as you're into it. As you're locked into tiptronic you should have a quick engine response and 9/10 all it needs is a bit more cojones.  If that fails try again and aim to turn slightly (remember, locked diffs! Tyre rotation is locked!) towards the mountain, never towards the drop, to try and steal some traction from the edges of the hollow that haven't been worn as much by previous drivers. It's gonna get noisy, and you run the risk of widening the hollow, but sometimes you just gotta conquer that bastard and get through

[Gaurav]

Welcome, @JamesBY this post is slowly awakening the mountaineer in me. You seem to be quite hands-on with rough patches. I remember Jebel Yibir is one of the nicest trails I have been to with @Jeh (WAKE UP) in 2015.

[Gaurav]

The morning view was priceless at Jebel Yibir.