TL;DR- I’m cross-shopping a US spec Discovery 5 td6 and Mercedes GL350 bluetec(X164 & X166 bodies). Any opinions are welcome

Hello all, hope all is well. Sometime in the future I’d like to upgrade one of our vehicles to do one that does several things well. Criteria is as follows

1) Diesel engine. This is a hard limit. I was infected with the diesel sickness years ago and if I had my druthers every other car I own, including sports cars, would be diesel powered

2) 3 row seating. My wife and I have 3 boys(yikes) and we will need all of the room we can get for the kids and all their stuff. We both envision taking camping trips. My wife wants a small camper, I’d be comfortable with tent camping but no matter what we need lots of room for “the stuff”

3) Some off-road capability. We live in the Denver metro so the mountains are close. We won’t be doing any major rock crawling but I’d like the capability for some moderate overlanding. I don’t know if anyone has heard of Otis the Porsche Cayenne diesel(definitely look it up) but that’s what I’d like to aim for.4) Tow capacity. Like I said above, my wife would like to get a small camper. I’d like to be able to put all the seats down and jam it full of a large Lowe’s shopping trip or tow a small-ish trailer at some point.



I’d like to stay away from a large diesel truck. It’s a little overkill for our needs. This vehicle will be a daily driver so I need decent fuel economy(hence the diesel engine). We do have a 3rd vehicle just in case something needs to be worked on for a few weekends.



What I’ve narrowed it down to

X164 GL350 bluetec

X166 GL350 bluetec

Land Rover Discovery td6

Full disclosure; I’m a mechanic and have spent a majority of my career working on Mercedes vehicles and I’d really really like to get back into a Mercedes if I can. The problem that’s coming up now is mostly about the engine. I remember PDI-ing new E320 CDI cars(that had the last straight-6 diesel engine) and that was the last of the incredible Mercedes diesels in the US, thanks to the EPA. I’m aware of the settlement with the bluetec vehicles. I’m capable enough that I can do a lot out of my garage so any work I’d need to do isn’t a big deal except for some really large repairs.

But I’m also aware of the, uh, frustrations that British vehicle ownership comes with. The disco 5 td6 is the only Land Rover I will consider owning. The engine being proven-ish from Jaguar and Ford, I know modern diesels suffer from the crippling emissions equipment. And the 8sp ZF trans that is used in dozens and dozens of makes & models is very reliable

The Benzes were available with an off-road package that included a locking center differential(I think) but it’s extremely rare to find one. I also know the Discovery is available with the rear locker but it also seems to be fairly hard to find and commands a premium over non-equipped vehicles.

For anyone who routinely takes their disco off road, how much more capable are the locking diff vehicles than the non-equipped ones? Obviously I want a more equipped vehicle but that may not be an option

Thanks to anyone that made it this far. Hopefully I explained what I’m thinking well enough. Any and all opinions are appreciated

 

I have had my D5, gas version over Hurricane Pass in the San Juans and I don't have the locking rear diff. It didn't even know it was climbing a rocky pass.
In fact, when I got near the top I realized I'd forgotten to put it in low range. It doesn't matter what's in front of it, it just keeps going.
So, if you are not trying to go on off road trails, any spec D5 will easily get you there (providing you have suitable tires). If you plan on forrest service roads, almost any crossover will get you there but maybe not as smoothly as others. I do know that with the air suspension I can easily ride down a rough forrest service road at a speed greater than many other vehicles without beating up the D5.
While many vehicles will get to the destination, the D5 might be more comfortable. I have no experience with those two Mercedes models. My last Mercedes was a 2002 ML320. It would get around fine but didn't really belong on the San Juan off road trails.

 

I wouldn't worry about the rear locker as much. Yes it does help, no doubt but the traction control in these vehicles is truly amazing (that said, you ACTUALLY have to use the various programs, seems like some people have difficulty understanding this concept). But compared to just about all other vehicles, the traction control in the D5 is seamless. You simply don't know its working. Just...works. In the LR3s and LR4s, cross axle was actually an issue but not with the newer D5s.

Obviously the rear locker option is the way to go, but yeah, its difficult to find one.

Low range with the 8 speed is a great combo. Off road 1st gear is so low. The diesel builds amazing torque at low range.

Your main issue with off road will be tires. Either get a vehicle with a set of 20" tires or go for aftermarket 18s. Aftermarket will run ~$350/wheel. Tuffant brand is what I'm leaning toward. But if you are gonna off road once a month or more, a set of these wheels and a good set of AT tires would be boss off road in Colorado. I've had very good luck with BFG ATs in Colorado.

If you do want to tow, best to find a vehicle already fitted with a tow Hitch. You can add it/have the dealer add it, but its a couple grand.

I would say, try to find a 2019 or 2020. Also try to find a "high trim" model (SE = lowest, HSE = mid, HSE Luxury "lux" = top trim). Also expand your search nation wide. I bought my CPO D5 from 500 miles away.

 

Thanks for the info, it’s good to hear that not having the rear locker isn’t that big a deal. Silly question though, can it be retrofitted? Or, can it be retrofitted relatively easily? I know anything can be retrofitted with enough $$.

This vehicle will be getting a second set of tires for off-road use eventually. The first few outings will probably just be into the national forest but I’d definitely like to get further away from everything than that

I’m also willing to fly anywhere in the country and drive back for the right vehicle.

What is the parts cost to add a hitch if I can’t find one already equipped? I’ve done bigger jobs than that in my driveway with my punk-*** hoa breathing down my neck

 

There's a 2020 D5 Td6 just south of Boston. It does have the locking rear diff listed as an option. The price is a bit steep as it only has 10K miles.
Link

 

You have three boys plus you and your wife and you are considering a new D5?

Get the GL. You will hate yourself otherwise.

 

This won’t be a new one, it’ll be an ‘18 or ‘19 and have some miles on it. Any that I saw on cars.com with the rear locker were at least $10k more. I’m not sure if that’s a true market representation but it’ll be a while before I get one with the locker if that’s really the case. But it really doesn’t sound like too big a deal. Good tires, smart driving, and a winch I imagine will be fine

 

@The D - welcome to the LR "club" first of all. Based on what you said, you were (are) a mechanic for Mercedes. I had 5 MLs and 1 GL in the last 15 years. All diesel. Every single one, had engine issues. Like: oil cooler, excessive oil consumption, dilution, and the last GL engine seized at 90k miles. Every single one was serviced and repaired at the dealership. I won't go into details, because you probably know, but it was the MOST unreliable vehicle(s) I have ever owned. I can go so far to say, that I told my wife, if she sees me into an ML / GL, to call the police - I must have been kidnaped. On the diesel LRs - there are few things to look at, in my opinion. Change oil at 1/2 intervals. Those engines for the year you want to buy do have dilution issues. They tend to over heat at high speeds - so they are very good at mid range speed, but they are not built for sport. Filters - change them more often than the book. Urea - never let it even 1/2 the tank. It will keep most of the common issues away ... years away.
Over all is a much, MUCH better engine than Mercedes, and it is much more reliable. The Discovery 5 is technologically years ahead of Mercedes. From suspension, infotainment, and many, many other features.
Now for the 3rd row seats ... yeah, that may be a bit tight. Have you considered a RR Sport Diesel ? I had one for 3 years and traded it for a new Defender ( gas, true). But the RR Sport had all the space I needed and it was awesome car. It was nice that after years of pain and suffering with the ML / GL to have a reliable vehicle. Rear Locking Dif - yes, it can be retrofitted, it will be very expensive, and not worth the time and money. I have a Disco 5 MY 22 now and a LR Defender. The disco 5 does not have rear lock dif, vs. the defender, and honestly I don't miss it. Would it be nice to have it ? yeah. Is it worth it ? unless you do hard core with the Disco, then probably not in my opinion.

 

Bah, it looks like my decision is made for me. I wanted to give the Merc every chance in the world but it looks like I’m going with the LR.

We don’t need the size of the Range Rover, we have a Honda Odyssey for our suburban kid hauling.

In order to retrofit the factory rear locker, does any wiring need to be spliced? Or is the body harness the same in both vehicles? I imagine you’d need the differential(obviously), the switch in the console, and either a different control unit or changing the programming? Anything else I’m missing?

 

The only option on my list I did not get was the diesel engine (the gas engine has not let me down so far though)... I just could not find one. I do have the rear locker and as the others have said, it just goes wherever you want it to go with no problem. I am in NC and have taken advantage of the Asheville/Biltmore Land Rover Owner's Day a several times and have learned a lot about the technology through Aaron and his team. I have two sets of wheels/tires too for whatever my needs are for the weekend. The Disco 5 is built to go off road and those that only use as a family hauler are missing out!!!

Keep us posted on your purchase... kj