Sponsored

WHY does Jeep not recommend Tow Dolly ?

JeepN3RD

Active Member
First Name
Sammy
Joined
Jan 5, 2017
Threads
7
Messages
36
Reaction score
37
Location
Greensboro, NC
Vehicle(s)
1946 Willys CJ2a, 2019 JLU Sport S
I wanted to start a discussion and I am hoping to attract some folks posting that have experience in this area AND would be even better if we have someone that has engineering knowledge about the transfer case in the JL.

Let’s start this off with...YES, on page such and such, Jeep says to tow 4 down or on a trailer. We have all seen that, and ANY time a tow dolly is brought up the thread is immediately deluged by posters who simply point to that fact as end all argument. What I would like to do here is think and discuss WHY this might be true?

One comment that will often come up is SOME of the JLs have a “full time” transfer case that is a different model than the rest. Therefore, Jeep simply took the easy route and said ALL Jeeps should not use a dolly instead of trying to tell their users the difference and explain ONLY certain models should and how to tell the difference, etc. For the moment I would like to ignore those transfer cases in this discussion...they are a minority in the JL world and “most” of us have the TCase with 2HI, 4HI, Neutral and 4LOW, that is the Jeep I would like to talk about.

So my first question is this...what is spinning / moving with 4 wheels on the ground vs just the rear wheels on the ground and front wheels on the dolly? The obvious answer is the front wheels...

Those of you that have towed 4 wheels down, would LOVE a short video from under the rig, IS your front drive shaft turning As you move? The reason I ask, I am not sure what type of hubs Jeeps are using now, if they are air/electric and only engaged when the Jeep is in 4HI or 4LOW? In the “good ole days” we had locking hubs and with those unlocked, the front drive shaft would (should) not spin at all when towing all 4 wheels on the ground? So...is your front drive shaft spinning?

I am going to assume the answer is YES...that front drive shaft spins with all 4 wheels down, TCase in neutral (auto tranny in park, manual in a gear)... THIS is where the actual knowledge of the transfer case will come into play. Is there something in the transfer case that is spinning via the FRONT drive shaft that is lubricating the TCase itself? IOW, this would be something that is ONLY being spun from the FRONT shaft but would NOT turn from the rear drive shaft?

IF that was true...THEN we might have our answer, WHY Jeep would only recommend all 4 wheels down / flat towing? Because with FRONT drive shaft turning the...such and such...turns and THUS the lubrication of such and such is happening.

HOWEVER....if this scenario above is NOT true...either front drive shaft is NOT spinning...or it is...but then nothing else in the transfer case is moving...(neutral) how could ONLY spinning the rear shaft cause an issue?

I think this is a good start, I am really hoping that we have some folks that can jump in and discuss this logically, mechanically, and NOT a bunch of comments from folks saying “well if Jeep said it...good enough for me...blah blah...”

Even MORE importantly, anyone that HAS actual tow dolly experience, JL, JK, etc... and I know some of you exist, I have seen 1 or 2 posts From you saying you have towed this way for xx,xxx miles, I DO want to hear from you as well.

I have MET a few of you at RV campgrounds, I see your Jeeps AND your tow dollys, this IS something that does happen on a very routine basis and yet I am not seeing a bunch of posts “I ruined my tcase from towing on a dolly...”. Have YOU seen any threads with that scenario...because they SHOULD exist if this was true!? (JL, JK.. I think for our purposes we can ignore the older TJ, YJ as the transfer case has evolved quite a bit since then.) Naturally if YOU have ruined your TCase from using a dolly PLEASE speak up, experience is appreciated!!
Sponsored

 

los Lobos

Member
Joined
Jul 12, 2020
Threads
0
Messages
19
Reaction score
25
Location
SE Louisiana & Texas
Vehicle(s)
2021 JLU Willys
Good thread that I hope leads to good discussion. I have no experience or knowledge in the subject but I'm following and hope to learn something.
 

chevymitchell

Well-Known Member
First Name
Shawn
Joined
Feb 18, 2018
Threads
94
Messages
4,268
Reaction score
10,228
Location
K-ville, NC
Vehicle(s)
2019 JLUR (Pain Train), 2022 2500 AT4
Occupation
Avi Engineer
I hate to be this guy, but this has been covered by dozens of threads over the last 14 years.

Jeep put that in the manual, not because there's some black magic going on inside the transfer case, but it's to prevent any accidental damage by people not knowing what they're doing.

This was also done for people needing their vehicles towed, so they could tell the tow driver to use a flat bed, in the case of a condition where the transfer case couldn't be put into neutral. It's a 4wd vehicle, so a lot of sales are going to be in the snow belt, a lot of accidents will be up there. It's just a preventative measure for every scenario where the vehicle needs a tow truck.

Putting this in the manual (For those that read it) should prevent any unnecessary damage to the drivetrain in the event you should need to have towed for some reason. The transfer case will also jump out of 4HI and 4LO into Neutral and vise versa if the lever isn't positioned in the detent just right.

You may have it in Neutral until you're merging onto the interstate and the lever jumps into gear then you have an issue.

Recreational towing, like with an RV, can be done with a Dolly as along as you do it right. The warning in the manual is just a preventative measure, not a rule.

You can remove the rear driveshaft if you're really worried.

The front driveshaft does not turn unless the vehicle is on and in 4HI or LO because of the FAD system.
 
OP
OP
JeepN3RD

JeepN3RD

Active Member
First Name
Sammy
Joined
Jan 5, 2017
Threads
7
Messages
36
Reaction score
37
Location
Greensboro, NC
Vehicle(s)
1946 Willys CJ2a, 2019 JLU Sport S
Shawn, great response and I agree this has been covered in various ways over the years, but really hoping we can create here a single comprehensive thread that might even become a sticky for anyone asking about tow dolly / Jeep Wranglers.

You mention, it is fine as long as you have put the transfer case into neutral and then some worries about it suddenly popping back into gear (4HI or 4LOW) which would cause immediate and sudden change / problems.

Of course this would ALSO be true for our folks pulling with all 4 wheels on the ground, correct? So any worries about the tcase popping from neutral to in gear would be true for towing 4 on the ground AND 2 on dolly!

With that in mind, what can we do exactly to “make sure we are doing it right” / and our transfer case is in the correct place, etc? I believe in the case of towing with all 4 down, Jeep recommends the Tcase in neutral AND the transmission in PARK!? I believe the reasoning for that is the way the gears are made, it is “easier” for the tcase to shift from Neutral to 4HI/4LOW if the transmission is ALSO in neutral. BUT...if transmission is in gear (park, or manual / actual gear) THEN that is actually safer, LESS likely for the tcase to suddenly pop back into gear (4HI/4LOW)

All of that to say... I believe we are on the same page here, that the warning appears to be to prevent various scenarios (snow, tow truck) but that there does not appear to be any mechancial reason towing with 4 on ground vs 2 on ground would cause any harm to the tcase.

Folks, would love to have more thoughts on this, actual video evidence showing movement of front driveshaft or lack thereof, when flat towing.
 

Mackskibum

Member
First Name
Dave
Joined
Feb 2, 2019
Threads
3
Messages
8
Reaction score
5
Location
Eastern PA
Vehicle(s)
2018 JLU Ocean Blue
I'm stuck in the same place also. The NV241 and NV241OR are effectively the same other than low range reduction. The 241OR comes in a Rubicon with manual front hubs. How is running with hubs unlocked any different than towing on a dolly? Either way, the front shaft is not spinning and the rear is.

Having looked at the 241 internals, the oil pump appears to be attached to the rear output shaft and therefore is spinning any time the rear wheels are turning. Wouldn't this solve internal lubrication issues in the transfer case?

It looks to me like if we place transfer case in neutral and manual trans in 5th or automatic in Park. It would be nice if someone like Novak would confirm what we believe.
Sponsored

 
 



Top