Almost at the OTP stage - 4.8 LOW consumption

[dieselfan]

So a nice patrol has caught my eye. Owner reckons he gets 6km/l while towing his marine boat at 100km/h. Car has 305/65's. I was told around 7-7.5km/l at 120 without load - sounds too good to be true?

He does have a Rob Green stage 1. ECU, pipe, K&N. Anyone heard of that type of consumption on a 4.8?!

[Chris Skinner]

That is definately better than expected fuel consumption.
I doubt you can tow a sea going boat at 100km/h at better than 5km/l (my boat/trailer weigh 3 tons and I get between 3 and 4 km/l, depending on wind, how hard I push etc. Have been doing this for many years with both 4.5 and 4.8 and my numbers are consistent.
On open road, not towing, (110-120 'genuine speed') I get between 6-6,5 km/l average, and with really careful driving (100-110) I can sometimes get 7!
A tip - when trying to get a a good measure of fuel consumption be sure that speedo readings - km/h and trip km's are as accurate as possible (eg I saw a 10% difference in both speedo readings when changed my tire sizes, and if one does not take this into account your consumption figures and comparisons really mean nothing). In my experience, when you suddenly have an unexpected good reading, this is normally due to strong wind vector from the rear, or measuring on a stretch of road that is mainly downhill (eg PietRetief to Pongola).
Good luck with the decision!!

[Peter Connan]

Tinus had a similar conversion on his car, and for a short while bragged about exceptional fuel consumption. But to maintain that, the filter had te be cleaned very often.

He has since reverted to the standard filter. I would not keep the K&N, no matter how good the consumption. It's not a racing car.

[dieselfan]

The air filter isn't open. It sits in a carbon fiber enclosure and then routed to the tjm snorkel. The reason I mentioned the tyre profile was to compensate for the speedo. So I suspect 100 on speedo is more than 100. Guy reckons he taps much less pedal due to torque.

Im just trying to see if theres honesty here or a too good to be true sale...

Admitably my dad took his patrol to SAC and kw at 2500 went from 75 to about 115 - if they being truthful. Previously with the camper on his max speed was 100 downhill. Now he easily manages 120 up that big hill after irene. Driving to kruger with the canopy averaged out at 8.5kml at 100 on speedo. Im sceptical of his dyno report though.

[Tinus lotz]

look IMHO that figures sounds to good to be true i have tried all the mods and went back to standard the resons being that the kn when going off road doesnt work need to clean every 1500km or even more just put the BIG DONOLDSON tipe back the diff is so small .
what did make a diff is to remove the big coffin box at the back and if there is a cat take it out . the engine gets air in and out mutch better .
we did a chip on mine but found that it doesnt work well at the coast so i bypassed it and left it that way
the better exhuast with snorkel and a light foot my figures are the same as Chris .
it is a heavy car and a big motor if you want horses you must feed them .
work your feul for a 4.8 out at 5 to 6 km per liter . when driving slow in thick sand you can look at 3 sometimes
love that 4.8 its a very good combo for sand rocks towing ect . buy it at a good price and just close your eyes when paying for feul

[Peter Connan]

Having said all the above, omong the 4.2 GQ guys on the forum, there is one guy who cosistently gets much better fuel consumption than the rest of us, and he has long-term figures to back up his claims.

Some motors just work better than others?

[Engel]

I have only been able to get 6.5 on the open road 120 speedo with standard tires. Boat 4 km/l. Town nice driving 5.

[dieselfan]

I thought it too good to be true. I joked with the salesman that if the trol did 7.5 he had better increase security...

Anyways tinus I dont fully understand why you say the kn is not good offroad? Its not an open filter setup. Its enclosed and routed to a snorkel. What am I missing?

Basically my disco is worth more than the patrol I want but I need a buyer...Otherwise id have the troll now ; (. Hopefully Ill Finance the patrol while I sell the disco. problem is being self employed...Finance is easier for my staff!

[Peter Connan]

The K&N filter has larger mesh size than normal paper filters, and relies on the oil it is treated with to capture dust. This dust is then washed of when the filter is cleaned, and new oil is applied.

But the dust absorbs the oil, and dries the filter. One (or both) of two things now start happening: either the dust/oil cakes start falling off, leaving areas of the filter unprotected, or the whole filter clogs up, making the engine suck harder and thus increasing the amount of dust that squeezes through.

K&N filters are great for racing cars, which are serviced regularly and where the engines are most likely to break long before they wear out, but I wouldn't want one on a working 4x4

[Tinus lotz]

Diddo piet I agree could not explain it better