Going to be purchasing a Defender 90. I see the towing rating is 7,700 pounds for the 4 cylinder turbo charged engine in North America.

i plan to tow 7,500 pound tow behind it on weekends for about 45 mins and twice a year 13 hour trip.

anyone have experience towing this kind of weight with this engine? Will I be miserable or will it get the job done.

any feedback appreciated, this will be my daily driver so for all other functions this motor is fine.

thanks

 

Is that a 7700 lb Gross Vehicle weight or a true 7700 lbs? I would be concerned more about the short wheel base towing such a large trailer. If your plan is to not go faster than 65MPH towing a trailer with a 5000 lb curb weight and 7700 lb GVW I think the 300 pound feet should be sufficient power, the ZF transmission is more than capable. I would probably also use some type of sway control towing with the 90

 

thanks for response. It would be a true total of 7500 weight with the load and trailer combined.

 

Dewman7770 .... I share DonMitsu's concern regarding the small wheelbase towing such a large trailer. Might be dangerous, as well as annoying.

As well, my experience towing with a 4 cyl. SUV at or near the weight limit is that over a 13 hour trip the heat sink capacity of the drive train was used up (including the extra radiator and transmission cooler capacity) and the flow capacity of the water pump was insufficient to not overheat. It was kind of interesting to note that the faster I traveled the cooler I was, due to the increase coolant flow rate -- I could keep it just under red line temperature wise -- but what a pain !! I traded out for a six cylinder (which meant capping the loading of power need below 70% of the capacity) and all was well.

A couple of other points:

1) are you towing on flat land or mountains ? It will effect the time it takes to reach the heat sink capacity of the drive train and shorten your time window to tow above the 70% (or so) design load capacity.
2) As a pertinent point of interest, there are two different ZF transmissions in the new defender: a lighter one for the 4 cylinder engines and a heavier one for the 6 cylinder engines, I expect they will both work well, but we do not receive any buffer on heat sink load margin on the critical parts of the transmission when buying the four cylinder engines. Both have the same gear ratios.

https://en.wikipedia.org/wiki/ZF_8HP_transmission The four cylinder uses the ZF8HP 45 transmission. I believe the HP70/75 model is in the six cylinder drive trains. I read a detailed expose on both a couple of months ago -- and the use on the defender, but I cannot locate in at the moment.

On another string, P300 vs. P400 maybe, I noted that I have on order a 110 P300, and hope to tow a one horse trailer (5000 lbs. max) for short hauls. I will start a string on how it goes, in a month when I receive the vehicle. As a backup, I have sold my 2016 Evoque and I am keeping my V8 2011 LR4 as a backup, just in case. The darn LR4 is just too useful to part with.

My suggestion is to consider the six cylinder. In the P300 vs. P400 string, I posted a link to a really helpful and interesting towing test video on the powerfulukltd website. It might definitely be worth a look for you.

 

this is really helpful.

i think I will go the P400 route but I am doing the 90.

what is really weird is on the builder the first edition 90 shows max towing around 8200 and the x dynamic with the same motor only shows 7700 I wonder if it’s a type or does the first edition have more tow capacity for some reason?

 

Take a look at allowed train weight in the detailed specifications -- this is the total allowed Gross Vehicle weight plus Gross towed weight.

I expect the amount will be the same for both versions -- but that Gross vehicle weight of the x dynamic is more, thus the allowed tow weight is less -- assuming the same allowed train weight.

 

here is the comparison. Very odd that the first edition weighs more and has more towing and GTW capacity for having same engine. Like I said I wonder if it’s a type-o

 

Folks:

I pulled some data and ran calculations to compare what I think is the operative comparable measure (pounds per horsepower) for the various vehicles we have discussed or possibly may wonder about. The number basically communicates the number of pounds each horsepower must move (or keep moving) at full rated HP output and gross load. I have limited my analysis to vehicles rated to tow above 7000 lbs, except at the end, where I pull some comparables to the P300 Defender. The results are helpful, maybe:

2020 Defender 110 P400 - 38.4 lbs per horsepower with full 1940 lbs. gross wt. and 8201lbs. towed
2020 MB G wagon (non - AMG) - 32.7 lbs per horsepower with its full 6615 (and small pay load of 1060 lbs) and 7000 lbs towed
2011 LR4 - 39.6 lbs per horsepower with its heavy gross wt. of 7143Lbs and 7716 lbs towed
2020 Land Cruiser - 40.6 lbs per horsepower with its heavy gross wt. of 7385 lbs and 8100 lbs towed

2020 Defender 110 P300 - 49.2 lbs per horsepower with large 2940 payload and 7716 lbs towed. To get the lbs per hp down to a competitive 40 lbs per horsepower, one needs to reduce the combined gross and tow weight by 2720 lbs. At a normal, "full" payload of 1500 lbs, this places the allowed tow weight at 5525 lbs.

Though not comparable to the Defender, I confirmed the accuracy of the numbers by looking at the Ford Ranger (270 HP) at its tow limit of 7500 lbs and 1650 payload and calculated a 53.6 lbs per horsepower (very pokey !)

The Toyota 4 runner 4.0L V6 (270 HP) at its 6300 lb GVWR, payload of 1625 lbs, and GCWR (train wt). of 11,300 lbs. comes in at 41.9 Lbs per horsepower. Right in line with the others.

Finally, for fun, I calculated that for my now former RR Evoque 2011, the 240 HP four with a GCWR of 5180 lbs (1,565 payload) and GCWR of 8,680 lbs calculates out all grossed out at 36.2 Lbs per HP.

As the logic bears out consistenty, I am going to treat my just arrived to the dealer P300 Defender as having an operational TOW limit of 5500 lbs, and call to duty my 2011 LR4 for anything above that number.

Enjoy !

 

Now that folks have been buzzing around. Has anyone tried to tow 7,000-7,500 pounds with there P300 yet?

 

Dewman7770:

I was towing 3000 lbs. today with my P300 Defender 110 -- on the interstate and on hills -- with only very easy breaking required. At this weight, the transmission in Drive mode was shifting a bit too much on hills to not disturb the serenity of the day, and in that case, I found non-manual Sport mode much more to my liking. I found backing up a gravel 12 degree hill to be more controllable and steady using Low Range.

I did not accelerate or decelerate up/down the interstate on-ramp in a manner to cause a 2 gear shift or use braking, so the rpms did not rise above ~ 3500/4000 rpm and under this conservative approach I certainly did not accelerate fast enough to make me comfortable in I-5 traffic (which I am familiar with having lived on the West Coast for 15 years). However, my present home interstate is very quiet, particularly on a Sunday.

Bottom line is the vehicle is driving just as I expected and in accordance with a power to a weight ratio evaluation where the limit of pleasing effectiveness will be reached/exceeded at ~ 5000 lbs., which is the most my towable boat, small RV or single horse trailer will ever weigh. I will use the my V8 LR4 for anything above that weight. I do not think I would need the LR4, if my Defender had a P400 in it.

Next step is for me to install a brake controller, before I try towing more weight or perform Defender tow tests during the work week.