DAY 1 ! FLAT TOW INFO

[mterlizzi1965]

Hello All,

Mike and Liz from Naples FL / TN. We just received our truck yesterday and other then its beauty , not much to say yet. But I do have one question that the answers and 'sales pitch' are completly different. Can this be safely towed as a toter behind our RV. But well get to it. If anyone is in SWFLA and meets up let us know were happy to have new friends were a jeep family

 

[[ Adam ]]

No, it cannot be flat towed.

 

[mterlizzi1965]

No, it cannot be flat towed.

Thank you. Huge disappointment as they sold me the whole sales pitch built for thet purpose with the hitch and front, prewired yada yada, well time to start a custom trailer build, o well lol!

 

[Tom D]

Theoretically it could be flat towed if the front wheels were off the floor on a 'spec' lift providing that the centre diff was unlocked. whether this would be ok for the transfer box in terms of oil circulation I don't know.

 

[anand]

Thank you. Huge disappointment as they sold me the whole sales pitch built for thet purpose with the hitch and front, prewired yada yada, well time to start a custom trailer build, o well lol!

The front hitch is also specifically not to be used for towing at any speed

 

[holdmybeer]

I wonder similarly. We RV and my Sprinter chassis can't tow more than 5,000 lbs so the Gren is out for me anyways. But a Super C or Class A easily tows vehicles bigger and heavier than a Gren. And I wonder if that's an option.

IMO, the limitation must be one of two things:

1. There's a physical deficiency in the Grenadier that prevents it from being safely flat towed with unlocked diffs, in neutral. The continent is full of Jeep Wranglers and GMC Yukons and Ford Expeditions being flat towed, four wheels down. Some vehicles need a manufacturer's package and some don't.

2. The Grenadier design team simply didn't think about the requirement and while the vehicle is well built enough, INEOS doesn't care enough about this segment to make it official like Jeep or Ford or GM.

(I'm not talking about using the front factory hitch BTW ... there are more appropriate ways to prep a vehicle for tow bar. It's been done for decades.)

 

[[ Adam ]]

3. It was not designed for it and flat towing it will damage the vehicle drivetrain.

 

[holdmybeer]

3. It was not designed for it and flat towing it will damage the vehicle drivetrain.

Sure, I see that as #1 above. e.g. insufficient cooling or oil circ compared to a Jeep, for example. Feels weird though, when mere Jeeps or 4x4 SUVs are great for flat towing. Where’s the weak link?

 

[[ Adam ]]

Sure, I see that as #1 above. e.g. insufficient cooling or oil circ compared to a Jeep, for example. Feels weird though, when mere Jeeps or 4x4 SUVs are great for flat towing. Where’s the weak link?

I would assume, like most product priorities it came down to cost vs perceived market opportunity

 

[Tom D]

It's not really INEOS at fault, its ZF, the version of box in the grenadier can't be flat towed in any of the vehicles it is fitted to. Other versions or previous versions of that box possibly can be flat towed..
It will be due to oil circulation in the box, I have a tractor with an older design, if you want to run the PTO with the tractor stationary the gearbox has to be in 4th gear and the shuttle lever in neutral, this is to ensure that the box is properly lubricated. If the gears aren't spinning there's nothing to slosh the oil around the box.

 

[pmatusov]

Sure, I see that as #1 above. e.g. insufficient cooling or oil circ compared to a Jeep, for example. Feels weird though, when mere Jeeps or 4x4 SUVs are great for flat towing. Where’s the weak link?

You have to be more specific while discussing a Jeep as an example.
Assuming we are talking about a part-time 4WD vehicle, the front axle and driveshaft can be mechanically disconnected from the transfer case. Typically the transfer case is also left in Neutral, and transmission - in Park (if automatic) or Neutral (if manual). In this case, when the jeep in question is flat-towed, the rear pinion of the transfer case is rotated by the rear axle, the chain (most if not all of the jeep transfer cases now are chain-driven) is in motion but lubricated by the ATF in the case, but the range selection gears are not connected to the output shaft of the transmission. As long as things can remain as I described, the jeep can be flat-towed as long as you want.
If there's a chance of some of that to reengage on its own, it's instantaneous horrendous news for the automatic transmission, or for the engine with manual transmission. Youtube has a great video of a Wrangler flat-towed by a Class A motorhome in low first.

The situation for full-time 4WD Jeeps (Grand Cherokee) may be different. The situation for full-time 4WD Land Rovers of the past (RRC, D1) is also different - you could technically flat-tow them with transfer case in N and transmission in Park - but I wouldn't trust the transfer case to stay in neutral forever. I don't even know if there's a detent ball that could keep the lever in neutral.

For the original poster - it's your decision if you prefer to have a 5600-lb curb weight vehicle on a trailer, or you can get under and unbolt the axle ends of the driveshafts and support them disconnected. I did exactly that once flat-towing a Range Rover Classic from San Diego to AZ - took me maybe 15 minutes to undo the bolts at the axle flanges.

 

[Tinerfeño]

If transfer box is set to neutral (and naturally center diff open) and ZF to park why it couldn't be towed? I can't see any technical reason why not.

Politics, responsabilities, etc. are other thing.

 

[holdmybeer]

You have to be more specific while discussing a Jeep as an example.

Thanks, sorry, you're right. I did specifically say "Jeep Wranglers" in my post before just saying "Jeep". I know there are different models of Jeep but the ubiquitous Jeep being towed behind hundreds or thousands of Class A and C RVs in North America is the Jeep Wrangler. What level of trim or option, I'm not sure, but success stories abound. Even within my own family and circle of friends, the Wrangler is a go-to behind an RV. It works. And it seems to share some "old fashioned" axle and 4x4 design ideas with the Grenadier. Thus, my question. But I get it. The ZF transmission seems to be at least one of the showstoppers.

The Grenadier is Built On Purpose... and I respect that INEOS' scope of purpose does not include flat towing. So I plan to Purpose the heck out of it in all the other ways.

 

[landmannnn]

Even if you could flat tow, what about the required 4 wheel braking system for the towed vehicle? This applies for most countries (USA, UK, Oz, Canada etc)

Or do people just ignore the regulations?

In many other countries you have to be a licenced recovery operator to flat tow.

 

[Eric]

Even if you could flat tow, what about the required 4 wheel braking system for the towed vehicle? This applies for most countries (USA, UK, Oz, Canada etc)

Or do people just ignore the regulations?

In many other countries you have to be a licenced recovery operator to flat tow.

You are correct, when you flat tow a car/vehicle in the UK, it becomes a "trailer" and must comply with trailer towing law. If over 0.75T it must have all wheel braking.

 

[holdmybeer]

Even if you could flat tow, what about the required 4 wheel braking system for the towed vehicle? This applies for most countries (USA, UK, Oz, Canada etc)

Sure but that part is relatively easy. Yes, you need one if your towed is over a weight threshold. Typically 3,000 lbs but varies by province or state.[1] Those systems are easily acquired and installed -- essentially variable-voltage remote brake pedal activators.

[1] https://rvibrake.com/en-ca/pages/flat-towing-law

 

[Krabby]

Make the mother in law sit in the Gren and instruct her to brake accordingly.

 

[holdmybeer]

Make the mother in law sit in the Gren and instruct her to brake accordingly.

High voltage signal running back to a mouth bit. Ok, that’s terrible. I’m sorry.

 

[Krabby]

The Jetsons/Hanna Barbera were so ahead of their times!

 

[pmatusov]

Even if you could flat tow, what about the required 4 wheel braking system for the towed vehicle? This applies for most countries (USA, UK, Oz, Canada etc)

There's a really neat thing called Brake Buddy. Pretty popular.
Trailer brake requirements are mostly by weight - most of the U.S. is 3000 lbs (everything is bigger in Texas, so it's 4500lbs).