GU 3.0 litreTD Manual Vs 4.2 litre TD Manual

G'day

I would suggest a comparison of torque and power curves. In the GU IV the manual 3.0 produces more torque than the auto.

The 3.0 will be more economical. The other decision will be in relation to the 3.0 alleged long term reliability issues in comparison to the 4.2 in the 3.0 litres latest form.

My choice was the 3.0 litre manual. On paper the 3.0 is a better engine with more power and torque. There is a substantial price difference also.

Regards

Paul

G'day David. I can't give you a direct comparrison with the 4.2TD, but I can give you first hand experience with my 2004 GU III 3.0TD.

I am very happy with the 3 litre, with some reservations. It has an abundance of power to burn, is economical (I regularly get 27-28mpg) and is as tough as old nails in the driveline/suspension. Now to my reservations.

The engine is brilliant, BUT, pre 2002 had their problems, and now seem to have been ironed out after that date. This is one high tech piece of engineering. I believe if you treat it like that you won't have any troubles (read, keep the service and maintenance up to date). I'd hate to think how long (or short) one of these would last if it wasn't serviced!

I have added a turbo timer that I use religously, and am adding a second fuel filter to mine and will keep a scrupulous eye on the fuel system after I found out the injection pumps are around the $8,000 mark to replace.

As with everything in life, you don't get anything for nothing, and if you want this power to burn, and brilliant fuel economy, then high tech engines are the only way to go.

I believe Nissan have earmarked the 4.2 for deletion from their range in the near future, so this topic will become a moot point.

Don't be scared off by high tech, it is the way of the future, and we will all have to come to accept it eventually.

Cheers

BTW, I can't see how Nissan can justify the $7,000 premium for the old 4.2 engine, I guess it is there for people who are hessitant in moving on with technology.

DavidT,
I have a 3.0 litre and I am generally happy with the vehicle. I have only had a limited drive of the 4.2. My main issues with the 3.0 litre are:

1. Throttle Surge - during offroad driving the throttle is too sensitive in low range and tends to surge as your go over obstacles. It has taken me some time to modify my accelerator foots use on the peddle to reduce the effect.
2. Low Down Torque - in my opinion the vehicle could do better with more low down torque. I find myself using low range more than the large engines in the group that I am travelling with.
3. Sixth Gear - the vehicle could do with a sixth gear as I try to keep the engine within its peak rev range (2000 - 2500 rpm), and that only allows me to do around 100km. To get to 110km or there abouts I start to get near 3000 rpm, and at this the speed the engine (which red lines @ 4500 rpm) is not as economical and sounds like it is working hard; which inturn may lead to the longevity argument that is always given for the 4.2, which lopes along at lower rpms.

If those three issues were addressed I would not have any complaints. I think the vehicle is better suited to touring rather than long stints offroading on difficult terrain. Having said that I have not been let down by the vehicle when I have been offroad.

Hope this helps.

Rich.

If you plan on accessorising the vehicle and keeping it long term go the 4.2, these motors are known to last over 500k. If you turn your vehicles over regularly then the 3.0 probably makes more sense.

My first patrol was a 3 litre, my current one the 4.2, both manual. Both were good cars, here's my brief summary:
1. Torque, torque and torque - the 4.2 has it off idle, the 3 doesn't
2. gearing - the 4.2 has 3.9 diffs v 4.375 on the 3 - lower revs for the same speed
3. stress - the 4.2 just does it easier, and generally at lower revs. You'll be less stressed too, as you realise the follies of the traffic light burn off - in a 4.2 you've got no chance!
4. I found the relatively higher revs when touring, help the 3 maintain the speed better up hills, as it falls back into the peak torque range thereby holding speed, the 4.2 tends to be operating at or slightly above peak torque, hence falls off the torque curve a little easier up the hill. I suspect this is also due to the relative technology difference, as well as my driving style.
5. economy - little in it 12.5l/100 in the 3, 13.3/100 in the 4.2
6. according to my wife - the 4.2 feels alot smoother
7. sluggish - yes the 4.2 is slower off the mark than the 3

For me they are both good vehicles - and they have both given my family plenty of good times. I love my 4.2 and wont be letting it go any time soon.

Cheers
Andrew

My slant on it is well known on here and I'd suggest a search would throw up a lot of responses.....
However, to recap my thoughts, here goes:
1). The 4.2 is a (relative) slug of a motor. It can be assisted to perform better with more $$$$ being thrown at it in the form of a 3" exhaust and a bigger turbo (latter I'm just about to do).

2). The 3L is a racehorse. They go like a scalded cat out of the box and if that's not good enough for you, add a chip to the electronics and they'll go heaps good..hehehe

I call the 4.2 a "truck" and the 3L a "car". They drive differently as far as I'm concerned.

So, it seems from the above that I'm putting the 4.2 down in favour of the more fleet-of-foot 3 litre.........nothing could be further from the truth.

It depends on what you want the machine to do for you. If you want a great town car for running around town and jaunts up the highway with economy in mind but also with great off-road capabilities, get the 3L.

If you plan to keep your machine for a long period of time, plan to accesorise it with a view to keeping for many years, plan to do a lot of slow-going off-road work, tow heavy loads etc and IF you don't mind being left for dead at the traffic lights......get the 4.2. My boy-racer days are well and truly behind me and I fit more into the 2nd category than the previous paragraph description.

I love my 4.2 and won't be parting with it anytime soon.

Cheers

Roachie

at last an original question that hasnt been asked a trillion times..

Having asked the very same question and been through the very ssame thought processes here's my 2 cents worth.
I ended up buying a new 4.2.. Simplistically it's cause it's bigger and simpler.. (KISS) keep it simple Stupid) The 3.0 is a 4 cylinder engine driving a 2.5 tonne vehicle. It gets away with it so well becuase f a lot of gizomos, bells and whistles which I don't even pretend to understand. It drives beautifully and gets up and goes.. BUT.. if you want to repair it inthe bush.. I hope you are a trained specialist Diesel Mechanic, 'cause heaven knows most bush mechanics would struglle withthe bells and whistles, let alone the parts for em.. So if you want a Patrol to get you to your weekend camp spot and to the office each other day, go the 3.0... just sell it before it gets too long in the tooth 'cause it's going to start expecting an arm and a leg to keep it going.. rememebr it's smal engine working very hard to do what it does..

Hi David T

I have a 3.0 litre manual, and whilst I am totally satisfied with the car, I am thinking I will go 3.0 litre auto next time.

I find the amount of gear changes that are required when either sand driving, or hill climbing are a bit annoying, and I find myself being limited to a fixed speed in whatever gear I am in (when situation isn't good to change gears)

I should highlight that I hate driving auto's (with a passion), but I think the gear ratios of the auto would put less stress on the motor when 4x4ing.

Also, the differnece in engine rev's between the manual and auto is really surprising.

Thanks

TonyG

I have had 2 x 4.2ltr Desiel patrols both have had 6 wheeler conversions to them the first did over 600,000klms all hard & overloaded. i sold it to a guy in SA who is still driving it with out a problem 1.5 years later, my 2nd patrol is a 2004 with factory turbo,Yes they our gutless with the standard Exhurst fit a 3" & it is a lot better but it will tow what ever you want. i put 1500kgs on its back & tow up to 4500kg behind, we our offan at a totall weight of 9000kgs as long as i dont push it over 110klms hr it will just chugg all day (Legal 6 wheeler conversion) i have never had to repair anything on them, both have done a lot of towing & off roading. Ive Just come back from a simpson desert trip (see feed back) and found most 3ltrs & 4cyd of all brands had problems on the big dunes & lot could not run the Aircon in the extreme heat or they had heating problems, as loaded as we were i found it easy even big red. I know others who have all had the 3ltrs & most now drive the slower 4.2 as they had a lot of problems with the 3ltr (they were the earlier models) the only Mechanical problem i have had is a clutch in the first was one Not bad when you cosider want i do to the poor thing I fitted a centre force clutch & that was it other than general maintance oil,tyres,brakes etc

David T

Mate I had a 2000 3.0L Auto, loved it in the hills & on the road but got to watching some of the 4.2's in the Nissan Patrol club I am in and in 2004 switched to a 4.2

The 3.0L I had did a motor at 57,000km's but Nissan replaced it at no charge & I was more than happy with it.

When I purchased the 4.2 I had the exhaust & turbo dropper upgraded to 3" & found the power difference was great.

I do a lot of towing plus off road work & agree with other comments that this lopping type of motor is great off road (did the Simpson in july & it just coasted along in 2nd & third low in the slow parts of the QAA line with a smooth & easy style that was great).

With towing I have just finished a 15,000 trip towing a bogie axle caravan, sat on 100Km/hr at about 2,200 RPM in 5th gear with the occasional drop down to 4th, & the vehicle did it easy (which is great on the driver) .

I have driven auto's for the last 30 years but thoroughly enjoy driving this 4.2 manual.

Only 40,000km's on the clock but not an ounce of trouble to date other than the alloy wheels (on both 3.0 & 4.2) need checking on a regular basis when travelling corrugated roads
Good luck in your choice

we had the 3.0's for work trucks ..... they are at best ok , they don't like certain deisel fuels and chuck hissy fits when you put a finer filter air cleaner in them .
we had a couple leak oil out of the turbo's , and one lasted a whole 30000 km before the rear cylander melted .

I own a 4.2 2000 gu wagon and the only problem i have had was only fitting in one beer while waiting for the oil to drain out every 5000km !

3 inch zorst , turbo dump pipe , K&N filter , and wind up the boost and it goes as good as i want it to . But then again if i wanted speed i would have brought a Porsche .

Hi davidT
I have owned a 4.2 for the last 17 years a Gq for 12years & a GU for 5 years & the only trouble I have had is the clutch went on the GU at 40k.Ater doing 19K in the GU I took it to Berrima for a tune up, the difference this made was incredible,before the tune I tried it up a local mountain in 4th gear just making it over the top at 80, tryed it after tune & went over better in 5th gear than it did before in 4th. The guy at Berrima reckons the Nissan 4.2 is a great motor but very poorly tuned out of the factory.Havent had much to do with the 3.0litre have heard of a few problems.I love my 4.2 & after the tune it flys.

I have owned two 4.2s one turboed one not.
My current is a 3.0 litre Auto with rock crawlers fitted to the transfer,the result?
Despite a replaced motor and turbo the very best of all worlds.
Great low range reduction with the rock crawlers installed,excellent economy,great road running performance and able to tow my 17ft van.
No way can the old 4.2s compare,yes maybe last longer but a pain to drive,particulary around town.
Regards

Hi again DavidT,
I was very disapointed when the clutch went in my GU at 40k.The GQ I had done heapes of beach work,towing & I pulled a lot of trees out with it & the clutch was fine when I traded it on the GU after 170k.The nissan mechanic reckon the GU clutch is not the same as was in the GQ(,weaker springs).It cost me 900 to have a new heavy duty clutch fitted.I Think the flywheel is solid as they said they machined it before fitting the clutch.
Regards garryn1292.

I have just done 10000 ks in a4.2 towing a 17 ft caravan total mass 1450kg. I have never been so disappointed with a vehicle as I have with this one. Every where i went even across the relatively flat Nullabor, I had the foot flat, max speed with tail wind85km. fuel consumtion 22ltrs/100. needless to say I have sold it, and bought a Falcon Ba. Now have effortless towing the same van, consumtion now 14/16 per100. This up through the New England Hwy, plenty of hills
cheers That was the last Nissan I will ever own
ringa