Thread: D2 towing and fuel advice AdrianS

Something that Adrian hasn't yet mentioned is, what tyres he's using on his V8?
(unless someone already knows this).

Has he 'over tyred' his D2? eg. 235/85's or something like that.

Obviously this then relates to torque at the wheels, but also his calculation for fuel economy as well.

I'm running slightly 'over tyred' 255/70's on my D1, and it's knocked the odo out whack by about -8%(to actual road distance), so my 9.5km/lt (by the odo) is actually 10.25km/lt(actual road distance).
ie. I'll do 700km by the odo, which turns out to be 756km of actual road klms and fill it up about 70lt or so(tank holds 89lt).
Most I've ever filled it has been 85lt.

The other thing Adrian mentions is that he's getting 250-270 out of a 95lt tank, but it's very rare to run a tank fully dry(unless you're unsympathetic towards the fuel pump) .. so the question is how many lt of fuel is Adrian actually filling up with after 250-270kms?

I have a V8 D2a and I only get about 550-600k's out of a tank of fuel, it is Not the most fuel efficient 4WD that I have owned But it is the most comfortable
When Fully loaded and towing my boat or empty towing nothing there isn't too much of a difference in the fuel consumption with my truck.
Hopefully the new tranny will vastly improve AdrianS's mileage.

Hi all Still stuck in halls creek the tranny harness didn't arrive now MIA in Aust post's system found another in Kunnunarra it's on a green plated D2 td5 2003 will it be the same I need a quick answer if possible Thanks

gut feeling is yes,, microcat will know,

worth a shot I reckon...


remember,, its only a wire that been worn through, or shorting.

any wire between those points will work--

Think trans cooler.. now.

The harness has a destroyed solenoid plug which the mechanic's "young bloke who's good with electrics" broke while replacing the tranny then tried to jerry rig together using bits left on the other tranny. He had previously admitted he hadn't done one before and declined my offer of the Rave manual and said he didn't need it. I found out what had happened when the mechanic rang me to say he couldn't get the tranny to turn the wheels and tried to blame the transfer box, I went over and started checking it when he admitted what had happened. I had brought down my laptop and my copy of the RAVE manual checked possible causes and went over the tranny replacement procedures with him. This brought several mistakes to light, ie he had put 2 litres of oil less than he should have, so as he fixed them I called up the schematics and plug layout found he had cross wired it and it still didn't connect in properly. I rewired the remains of the plug which got it into limp home mode drove back to the caravan park did more research and determined the harness was the best option. I've had the owner of Whyatts landrover in Geraldton roll into town he's also determined that this is the most likeley cause also Triumph Rover in Adelaide agree with the diagnosis. So until I can get a intact harness I'm stuck as I can't clear the fault, I've exhausted local sources they all have D1's so no electronic auto's and now the one from SA is MIA in Aust Post's system somewhere between Perth and here. Just another glorious day in "Hells Crack"!

You've done very well Adrian,,
now its up to Oz Post,,
sigh,,

At last a little bit of sunshine today finally got a difinative nanocom diagnosis it confirmed the harness fault so we wait with ANTICIPATION the arrival on Monday (PLEEESE!!!!) of the replacement. Then it's farewell HELLS CRACK!!! hello Doondoon or Kunnunurra depending on day and time of departure.

Originally Posted by PhilipA

Well Pedro, I am aware that the V8 locks up lower than a D5, or should I say I thought I remembered but didn't want to complicate things further.
But the principle is the same- stay in lockup.
In any of the variants, if you have your foot to the floor it will unlock, and if fast enough will not kick down.
A 4.6 will not have as much torque as a tuned TD5 at les than 2000RPM so will probably drop out of lockup more readily.
I know my highly tuned RRC 3.9 even with Thor manifold Unichip etc (and it had as much torque up to 2500 as a 4.6 ) was nowhere near as good on hills as the TD5 while towing my camper trailer.

With regard to fuel economy, the 4.6 may be better in third where it may be able to maintain closed loop ( to about 1/2 throttle) , than with high throttle openings at low revs which will take it to open loop. Windage is a major cause of the requirement for power so the faster you go the more fuel you will use. IMHO about 80-85 is the go . With regard to fuel economy, all RV8s are renowned for poor economy while towing but are better than say a Patrol petrol or LC petrol. That's why 90% of tow vehicles you see on the road are diesel. LOL . I think 20-25 L per 100 Km is about right Vs say I guess 14-17 in a diesel in the same circumstances.

So experiment a bit but remember lockup is your friend.

BTW Castrol Transmax is about $90-95 for 4 litres at Repco. I recently did a filter and double change on mine which cost $200, but cheap compared to the alternative. That is DIY .
Regards Philip A

Phillip the 3.9 wasn't as torquey as a 4.0 (due to the 4.0-s Thor manifold the D2 was 20nm higher at the same revs 2600rpm). I had a well tuned high comp 4.0 d2 with a Crowe tow cam and other goodies and it wasn't anywhere near as torquey as my high comp 4.6 D2...which at 2600rpm is rated at 406nm versus the 95 D1 3.9 320nm at same revs....pretty impressive max torque difference but what is more impressive is the low end torque of the 4.6 through its long stroke. I can't imagine any 4.0 with the same torque as the 4.6 Thor much less a 3.9's manifold.

The stock td5 develops nearly 100nm less than the high comp stock 4.6 Thor at 2600. Td5 develops 90% from 1450rpm.

Torque holds you on a hill and power allows you to pull up (bit of both). Here the Td5 is peaky making 100kw at 4200 (well under that in Defender...) and the 4.6 Thor 166kw at only 500rpm more...and at 4200 would be making some 60kw more...

So the Td5 would need some serious work to get to a 4.6 power and torque. Id like to see it...

Cheers