Ok so td6 or si6?
 

No issues at all with my diesel and I love it - 26.6 MPG since ownership (6700 miles). Up to 40 MPG on one longer highway segment - but typically around 35 MPG. Quieter that gas. Fuel prices are about $.60 per gallon cheaper since the gas is supposed to run on premium. I paid extra for the diesel on my 2018 SE and will save the cost after 2 years of ownership given my typical mileage. Diesel tows better - lots more torque. I don't know why you would buy a gas model other than it was an impulse purchase at the dealership and you were not willing to wait for an order to come in.

Check out the Gauntlet towing test for the 2016 Range Rover Sport Diesel by The Fast Lane Truck on Youtube. This is the same engine as the Discovery Td6.

Unfortunately I'm not ordering a new one but looking at what's currently on lots. Trying to stay at $55k or less which there are some out here it's just been tricky finding something with a towing setup. If I go new there's several that are under that price with the towing setup but gas.

I'd go with the diesel if you're going to be towing. It's got more torque and better mileage under load.

The diesel would make absolutely no sense for me and would be a complete waste of premium for the engine. Also diesel costs more than gas here. Add in the extra maintenance, etc.

With that being said, I think the diesel is an awesome set-up nd is absolutely right for some - just not my situation. You have make the call based on your personal scenario.

The "very short oil change interval" is how long? I was used to changing oil every 3-5K miles in my previous vehicle and my Td6 engine is easily surpassing that requirement. I use my Td6 Discovery as a daily driver and do many shorter runs around town with stop and go traffic and the auto shutoff function engaged. From my research it sounds like the 4 cyl diesel engine in the Discovery Sport has had problems, and sensors have had to be reprogrammed (software updates) on multiple JLR vehicles, but problems have not been directly attributed to the Td6 design. I don't know what the "bad rap" is, but if you have owned driven the Td6 you will save tremendously over the life of ownership, particularly if you follow the JLR guidance of running premium in your gas engine vehicle to get the full horsepower rating. To each is own, but I have found the Td6 easy to live with and a great power plant, exceeding my every expectation.

Been loving my 2017 TD6, no issues thus far. The recommended oil changes are at higher intervals than the gas oil changes, only difference is they replace the fuel filter on each change vs gas which does it every other. Only addition I really see for the TD6 is the DEF fluid that has to be filled. Still haven't had to fill mine yet though.

I'd have thought this will depend a lot on how you use the vehicle. The Si6 has a ton more power than the Td6 (340hp vs 254hp). And is much quicker - 0-60 in 6.1s vs 8.7s. So it's a totally different driving experience. I'd say the Td6 is slow around normal traffic

But if you tow then the over 100lb-ft more torque - and the fact you get it at under 2000 rpm makes the Td6 vastly superior for towing

For fuel efficiency you have to do the trade off based on relative cost of petrol/gas vs diesel where you live and the cost of the vehicle

The DPF system has been driving people crazy in some of these Diesel engines. Not sure if that's fixed in the current ones

I was referring to multiple threads like these that I saw in regards to the Td6 in the D5.
https://www.disco5forums.co.uk/viewt...=4343&start=10

Likely more relevant for colder climates and people doing mostly short trips, however something that other may want to consider in their decision. The cost of oil changes on the D5 is quite a bit more than the typical lube job many do at 5k miles, but with expected intervals in the 15k range it is not too bad.

The Td6 does seem like a great option for many, but it is worth looking at all scenarios when making a purchasing decision.

I'd say that you haven't driven the Td6 to think that it is "slow around normal traffic". Paper is not reality and the area under the torque curve is impressive - which equates to acceleration and pulling force - not peak horsepower at an unusable RPM. I drove both vehicles, evaluated the experiences and the choice was obvious. The gas engine is weak up hills and sounds like it is coming through the hood under hard acceleration - easily demonstrated on a highway on ramp and up the hill to my dealership (but it is the more economical choice on the front end of the purchase). The diesel pushes you into the seat and quietly accelerates without the drama and keeps accelerating up the hill. I ordered my vehicle and waited 4+ months to get exactly what I wanted. In the process, I avoided many of the electrical and "in control" gremlins associate with the "options" on the HSE and Lux versions of the vehicles (regularly reported here) with vehicles readily available at the dealerships. I can't speak to a D5 Td6 oil change cost since they are included with my vehicle, but the interval to the first change is 8000 miles and I understand during each change the fuel filter is also replaced - perhaps this is why it costs more?. I can speak to the DEF as I have refilled the vehicle and it is pretty straightforward and much more economical and readily available than anticipated - about five minutes and I'm good to go for another 3-5K miles. The display tells you when to refill and gives you warnings every time you start the vehicle - kinda idiot proof. I live in Colorado at over 7000 feet elevation and while I do have some stop and go traffic, by no means is it as bad as the northeast corridor along I-95 or in the Boston area. I can also appreciate where diesel may not be as readily available in an urban environment, hence the choice for gas. Lots of decisions out there, just suggest folks that are looking to purchase look at all the options and avoid the impulse purchase at the dealership and get what they really want. Also consider how long you intend on keeping the vehicle and how much you will drive it. The vehicle I replaced has over 350,000 miles on it and still running strong (original engine and transmission - never rebuilt). But over the life of the vehicle, fuel costs become one of the single biggest expenses depending on how much you drive. Good luck with your Discovery purchases and keep them on the road as long as possible.

Yeah I will echo the TD6 performance. From 0-45 mph there is turbo lag, if you try to accelerate fast, it just doesn't happen. From 40+ this thing becomes a beast and pushes you into the back of your seat. I went from a SUV that would do a ~6.5 second 0-60 and honestly I am not really feeling much of a difference, when I need the speed to pass or merge it is there. I certainly didn't get my Discovery so I could beat a sports car off the line, I would get a F-type for that :)

I drove both in an urban setting and found the Td6 to be a lot more sluggish. I'm not basing that on theoretical peak horsepower - it was very noticeable to drive. And If you look at the stats it is definitively slower:

0-60mph is 6s in the Si6 vs. nearly 9 in the Td6. At 50pc longer I would say that 3s slower to 60mph a very real world difference.

Similarly in passing (45-65mph) the Si6 is 3s vs. 4.7s in the Td6.

I'm not knocking the diesel. Think it's a great engine, terrific fuel economy and excellent torque if you want to pull a heavy load. But in day to day driving the performance difference to me is substantial

In the end I suspect this will be a very personal choice. If one were 'better' then they wouldn't have them both - instead there are real and meaningful differences that you have to decide what fits for you.

I own a TD6, but have had a Si6 as a loaner for over a month (don't ask why).

I hate the Si6.

From a dead stop the 6 is sluggish, throttle response is horrible and when it comes on it does so in a hurry. I also find the TD6 to be easier to modulate and has amazing boost on the highway.

Plus I usually get 26+mpg in the diesel around town.

Interesting you say that on the throttle response. We have the same issue with our new Si6 which makes it much less than fun to drive. Press throttle - nothing, nothing, nothing - then suddenly it starts to go. I assumed there was a mech issue (it's going in to be checked) - but a number of people have mentioned the same...

From a dead stop there is no lag or lack of response in my gasser. The issue is when I am coasting in a round-about going from 2nd to 1st and then push hard - that was my point in the thread on the transmission issue

Thanks Hayseed. That's what I thought you said but others on your thread seemed to suggest they have the issue pulling away from stationary

ToiletDuck - totally agree and it's in today being looked at. Will report back. It's not engine lag (like turbo lag) - it's more that it just pauses. Unclear if transmission or throttle response - but hoping they can fix it!

It sounds like transmission behavior. Trying to decide if one gear downshift is enough or needs two... In a diesel, there's no such hesitation, due to limited RPM range.
Have been using an F-pace as loaner, have the same hesitation.

It is a transmission issue but nothing to do with gas vs diesel (unless they are using two different transmissions). I had an FPace for 40k+ miles and no hesitation at all. It is a Discovery thing.

Had a similar issue with a 2010 Escalade, had a 400HP 6.2L V8 with the (then) new 6 spd auto. At certain speeds when hitting the gas it had a lag where the ECU and transmission was trying to decide on a gear while cutting power to the engine. Definitely not an engine issue as those engines have a ton of power at any RPM, but rather a transmission and engine ECU programming issue. I would think they will program the Si6 very different from the TD6 on shift behavior to adapt for the different engine power profiles.

Waiting on my 2019, and hoping the issue is better or resolved by then (or at least have an update to fix it). Sounds like a pain.

That is why I want to reset my ECU. I think I broke it in per instructions and somewhat softly. Having driven it harder lately - it seems that some lag has gone away.

I was trying to make a point on the downshifting algorithm.
Two cases for comparison purposes:
Si6: --> gas paddle pushed down hard --> ECU first think to down shift to 6, then hesitating about why not shift to 5 instead --> delay in the thinking/ramping RPM process
TD6: cruising RPM 1800 @ 7th gear --> ECU knows max RPM is 4-5K --> ok, shift to 6th and that is all I can give

On the other side, this TD6 seems to ramp up in RPM fairly quickly, unlike typical diesel engines...

On the side, the paddle shifter can be set to work in both D and S mode, this is proven to be effective to avoid unwanted tranny hesitation.

My t/m hesitation is only 1st to 2nd and 2nd to 1st. Perfect shifts in other gears.

That is good info. Perhaps more spirited driving from new will be a good thing, the instructions just state not to floor it or high rpm while cold :driving:

The major hesitation I get (and it is not every single time) is in first or second gears. I originally thought that the issue was a 2nd gear start, but even shifting into Sport mode (which should mean 1st gear start) it will still bog.

There doesn't seem to be any rhyme or reason to it. Standing start, creeping start, seems to happen, or not happen, during all.

How long have you guys been in the vehicles? I had this happen to me for the first 500 or so miles after I bought used ~10k miles, then it stopped. I am not sure if my driving style has changed or if it "learned" how I drive, but the gear 1-2 or 2-3 shift that seems to lurch, no longer does this. I have put on about 2k miles.

I've been in this D5 Si6 for almost two months and have put about 3,500mi on it.

Ahh okay, I am a TD6 so I don't think my experiences apply.

I actually OWN a TD6, which is why I initially noted the difference.

The Si6 I'm driving is a dealer loaner.

I just picked up a brand new Si6 and am experiencing the lag, particularly going from 2nd to 1st. I have no issues starting from a dead stop - the issue comes on when I am already rolling (for example, making a right turn at a stop sign that I don't really stop at) - there is a very dangerous lag where the car does nothing. I am going to try and use the accelerator more aggressively and hopefully it will learn something...

I'm guessing it's refilling the DEF regularly.