Nissan GU 2.8L TD compared to 4.2L TD

Coyote,
I've had my GU 4.2TD for almost 5 years now and have always kept meticulous records of fuel purchases and distances etc. My speedo is out by approx 7% coutesy of the slightly bigger tyres I run. Over the life of the vehicle, which has included a reasonable amount of low range work, (Simpson Desert, Cape York twice etc etc) I have averaged nigh on 16l/100 klm. My vehicle has always had a roof rack too, and given that the speedo is out by 7%, the real kilometers I have travelled (speedo shows 170,000) would be 181,900; so my real fuel economy would be closer to 14.8l/100klm.
I saw on the Trading Post in SA last night on the web, that there is a wreckers in Adelaide that has a 4.2 diesel for sale for $3,950-; I don't know any other details.
Just also be aware that you are gunna have to change the gearbox over too, as the one they used in the 2.8l patrol is not up to the task.......the 4.2's gearbox would be about the same weight as the motor in the 2.8!!! ;-)) Okay, so I'm exaggerating just a little bit!!
I've never driven a 2.8 Patrol, but from what I've heard of them, I wouldn't want to either.
As for the 3L Patrol, the latter ones from 2002 onwards, seem to be holding up very well and I would not try to talk anybody out of buying one. I would not own one myself (but that's only cos I'm a boring old f@rt who is too set in his ways).
Cheers
Roachie

If I recall correctly, the 2.8TD uses the same gearbox as the RB30 petrol version - a Nissan 300ZX sports car box. Nice and smooth, nice and easy to change gear.... as long as you don't tow in 5th. If you were going to change engines, you'd be up for a new g'box out of a 4.2, along with different engine mounts and gearbox cross member.

Shafts - rear definitely and probably front. Diff ratios are different too.

I just bought a whole 4.2 turbo diesel GQ (aftermarket DTS turbo) for $10k with 295k on the clock. Body in great nick - never been seriously offroad.

I'd sell the 2.8 (plenty of people still want them - same as the RB30) and but another. Then you can go though the same fun I am swapping all my suspension and accessories over.

Cheers
Chris

Hi Coyote,

I'm not sure whether you're planning to change vehicles or do an engine/transmission swap to get a 4.2, but either way it's lot of hard work. Have you considered getting the most out of your 2.8? If it's stock standard then you have quite a bit of scope for improving performance (and, considering it's woeful now, probably better economy too!).

The 2.8 has a conventional VE-type injection pump with a manifold pressure compensator and responds very well to the usual compensator adjustment techniques. Ask around for specialists in your area who do this on Nissans. A free-flowing exhaust system will help too, if you're still on the standard system.

What really surprises me though, is the shocking fuel consumption you're getting. If I had a turbo-diesel chewing through 17L/100km solo, I'd burn it! That's 4L petrol type figures, IMO. Are you sure there's not some other problems here? How's the general maintence situation? Clean air filter, timing and tappets spot-on, no dragging brakes, etc.? Or do you cruise everywhere at 130+ km/h?

I've kept figures on our Discovery 2.5L Tdi for the last 90,000km, including at least 40,000 towing caravans. Our overall average over that distance is 11.7L/100km amd our 'towing' average is still 13.1L/100km. Regularly uses less than 10L/100 solo. And this is with an injection pump tuned to give maximum acceptable EGT at full load, not economy.

Idon't understand your feed back as I have a 98 Nissan TD 2.8 and it is very frugal on the fuel consumption. You must be towing a really heavy load or one that has a very large wind resistance.
For very heavy loads the 2.8 is not for you - but for camper trailers / garden trailers etc no problems.
My truck is very responsive at higher speeds and the economy is excellent @ 10 - 12 litres per 100 k's.
I have travelledover 230,000 ks with no major problems!
Towed the CT in 5th all the time - no problems.
With the expensive fuel prices the small 6 is the way to go.

Hi coyote, I have a current mod 4.2 T/D it does around 15L/100klm only 4k on it so far hoping the consumption will be slightly better as it gains more klm, though from everyones comments I wont be holding my breath...

As far as my thoughts between 3l & 4.2l mmmmm... I'm greedy bigger is better..
The 3l are a good fairly advanced diesel engine with great power, though high revving, I wonder about the longevity, hence my choice for the 4.2L...

Good Luck mate...

Regards,

Babs.

I too have difficulty in understanding the fuel consumption on this particular vehicle. I have a 1998 2.8tdi Nissan GU and have keep meticulous fuel and servicing records since I bought it with 43,000kms on the clock. It now has 171,000kms and over that distance I have averaged 12.33L/100kms (like Roachie I too do a lot of off road work over long distances 2xCape York etc). You either have something wrong with the engine set up or you need to buy new boots - your right one is far to heavy.
I also disagree with the viewpoint that it is a slug on the highway. Mine is quite capable on the highway and for that matter off road. It is a bit (no a big bit) of a slug low down but overcoming that is a matter of driving technique.
Before spending too much moolah find a good diesel mechanic to have a look at the donk.

Cheers
Pete

Well it looks like I have some probs with my little 2.8 to sort out.. compared to the 4.2 it isn't doing much better on fuel and it sounds like mine is differnet form at least two others.. admittedly I am running bigger than standard rubber and it is 4 inches higher and a roof rack but I can honestly say that I am not a lead foot. I gave that up when I bought a 4WD.. I sit on 100ks on the freeway.

Hi -- Definately something wrong with fuel economy / calculation.
Had my 99 model since new, no problems at all. get 11 --12 / 100 klms.
Motson chip fitted, great on the highway, sluggish low down, need to keep reve right up in sand / mud to get through. Have auto locking front diff, BFG all terrain's.
Bobw

Coyote
I have a 2003 4.2 Patrol. The roof rack is permanently fitted plus dual wheels on the back. I run a K&N air filter with a snorkle and 3 inch mandrel bent exhaust.
I regularly tow a caravan and have just returned from a 4 week 6000km trip from Queenland to Victoria and back(towing the van) plus 4 adults and 1 child, plus running an 80 litre Waeco fridge. My fuel usage for that trip were 1282.51 litres for 6704 kms (odometer) or 6641 kms (GPS). This equates to 17.31 l/100km, 5.92 km/l or 16.73 MPG. Worst figures was 21.69 l/km, best figure 13.74 l/km. My average fuel without the van since November 2004 are worst figure 15.62 l/km and best figure 10.92. There's quite a bit of variance but the conditions also vary.
For towing you can't beat the 4.2 - I towed the same van with a 1996 130 Defender (TDi), the fuel economy was better but the car was really pushed to tow the van, with the airconditioner on, and go uphill (or even overtake).
Hope this helps
Peter