Thread: Tow vehicle motors

Originally Posted by Lotz-A-Landies

Diesels are different, however the comparison of the 300TDi 4 cylinder and a modern diesel semi trailer is like comparing chalk and loungeroom furniture. It wasn't so long ago that diesel trucks always held up the traffic and crawled up mountains at walking pace. The modern semis have huge 500+ BHP turbo V8 engines and more importantly are designed to tow such loads. The 4 cylinder 300TDi needs to have additional cooling to safely tow the weights you are discussing.

Diana

And they average 4 mpg, my Mack was a 285 Coolpower and it averaged 7mpg, always a downside for Power, Regards Frank.

And they average 4 mpg, my Mack was a 285 Coolpower and it averaged 7mpg, always a downside for Power, Regards Frank.

Considering the huge weight, that's pretty amazing really. I've had cars that only get twice that economy.
Tony

Originally Posted by Outback 1

i have recently towed about 2.5 ton with my disco from dubbo to qld at times on steep climbs i was down to 60 kmh and yes it does affect the economy .If you are happy to just cruise along in no hurry the Tdi is the way to go as it is more economical than the v8 to start with

This was last Sunday. We calculated the gross trailer mass at something between 3 and 4 tonne and would have loved to have done 60 KPH up Mount Victoria but it wasn't the case. The auto transmission temp just would not cope with the load so we took it very easy.

Whatever you power the tow vehicle with the ideal transmission is a manual.

The Rangie is a 4.6 efi on LPG so the fuel costs at 60c/litre would have been comparable or better than a diesel 300TDi at $1.30+/litre.

Diana

Originally Posted by Lotz-A-Landies

The Rangie is a 4.6 efi on LPG so the fuel costs at 60c/litre would have been comparable or better than a diesel 300TDi at $1.30+/litre.

and how many km per litre do you get on gas?

Originally Posted by Guru036

G'day all,

I was just ready the thread in in tech about tow vehicles and it got me thinking about mine.

I tow heavy car trailers with buggys (probably 2.5T - 3T) with my 3.5L EFI V8 Auto rangie. It tows well and gets about 300kms per tank (about 21-22Lper 100km) It holds road speed pretty well too.

But I have thought about putting a 300tdi in it with a 5 speed manual (as I already have the motor and box) but I'm worried that doing the conversion (which will cost me around $1000 to do myself) won't be worth it in the long run. How well do the 300tdi's tow? I would be keen to try one towing to see how they go if anyone is keen?

I'm keen for the economy, but worried about losing alot of road speed

Dave, if you want you can see how mines goes - but would recommend the Auto with the Tdi for towing, mines been used as a tow mule many a time :



I did have the standard tyres on this time though.

LRH

I think the 4BD1-T would be the best LR engine for a tow vehicle.

Originally Posted by Tank

And they average 4 mpg, my Mack was a 285 Coolpower and it averaged 7mpg, always a downside for Power, Regards Frank.

From memory, the roadtrains around here use about 1 litre per kilometre fully loaded on the highway. Sometimes a little less.

I would keep the V8 and spend the money on gas injection and set up your gearing for towing.

I wouldnt go manual with the TDI for towing really heavy loads as with the auto you get better torque multiplacation from the torque converter and it also alows slippage to get the turbo spooled up where the manual you either have to take off really slowly or rev crap out of it and burn out the clutch.

The 4bd1-t would ba a much better conversion with a manual or auto conversion for towing but the 300TDI auto will tow significant loads all day everyday with out too much dramas but as said before, auto cooling and engine cooling is very important.

Make sure what ever engine you have if your using an auto you fit an external trans oil cooler and towing large loads you take off in lock low (manually selected 1st) to limit load on the sprag (one way clutch).