Thread: Disco 2 TD5 Auto box and towing +best for engine

From my experience with heavy towing (BIG vans), I'd suggest locked in 3rd unless you are on the flat or running downhill, then move to D. As far as best for the engine on a heavy pull, keep the revs up to that the gasses are flowing through the motor faster. Better to manually drop to 2nd and rev at 3000 than lug in 3rd at 1800, don't be afraid to sit in the left lane and take your time climbing the big hills. Maximum torque is at about 2000 in a TD5, so balance torque with revs dependent on the terrain. Install an extra auto cooler preferably. Change fluid and service trans more frequently if heavily worked. ECU upgrades make a BIG difference. Regarding heat, make sure that your fan hub is in good condition, and clean the radiator fins thoroughly. Nanocom shows engine temp, but there is no sensor to measure Trans temp. There are various sensor and gauge kits available, but I can't find a link right now.

What are people's thoughts on using low range on really steep pulls like Toowoomba or Moonbi? My TD5 auto pulled my 2T van up Moonbi screaming in 2nd. If I had known it was so steep for so long I would have gone into low range at the bottom to spread the torque multiplication between the main and transfer boxes.

Later I did the Toowoomba range for the first time. Not knowing what it was like I went up in low range, still screaming but knowing that the main trans was not working as hard as it would have been in high.

Stephen.

Originally Posted by StephenF10

What are people's thoughts on using low range on really steep pulls like Toowoomba or Moonbi? My TD5 auto pulled my 2T van up Moonbi screaming in 2nd. If I had known it was so steep for so long I would have gone into low range at the bottom to spread the torque multiplication between the main and transfer boxes.

Later I did the Toowoomba range for the first time. Not knowing what it was like I went up in low range, still screaming but knowing that the main trans was not working as hard as it would have been in high.

Stephen.

I don't know those particular hills, bit I once pulled 3.5ish tonnes of van up the hill out of Bombala NSW, which was ugly, got to about 25km/h by the top. Personally I'd not use low range, as in the TD5 at least, this radically alters the shift and throttle mapping and would make it a lot harsher. I reckon that if you can keep the revs up in the torque band of 2.2k or so, the Disco's will pull anything. I use low range for all very low speed maneuvering though.

Originally Posted by StephenF10

What are people's thoughts on using low range on really steep pulls like Toowoomba or Moonbi? My TD5 auto pulled my 2T van up Moonbi screaming in 2nd. If I had known it was so steep for so long I would have gone into low range at the bottom to spread the torque multiplication between the main and transfer boxes.

Later I did the Toowoomba range for the first time. Not knowing what it was like I went up in low range, still screaming but knowing that the main trans was not working as hard as it would have been in high.

Stephen.

Low range on a big downhill such as the Toowoomba range you've mentioned may be a good call. The engine braking you'd achieve should, I'm guessing, be superior to that you'd get if you stayed in high range and locked the 'box into 1st.

I'm keen to know others' thoughts on this too. Not that I do any towing at the moment. Still, it's useful information to have.

Originally Posted by bell1975

Low range on a big downhill such as the Toowoomba range you've mentioned may be a good call. The engine braking you'd achieve should, I'm guessing, be superior to that you'd get if you stayed in high range and locked the 'box into 1st.

I'm keen to know others' thoughts on this too. Not that I do any towing at the moment. Still, it's useful information to have.

I'd be inclined to agree, I was always taught to use the gearbox over the brakes when possible, because assuming you treat your gearbox correctly then it's designed to take it, much more so than brakes. Engine braking in L1 is excellent I find, careful use of the brakes helps even more.

in regard to low range and big hills, it would seem that it would be a reasonable thing to do whilst going up if your not going to be any slower in LR.

It may depend on the converter locking, I have only noticed what I thought may have been overdrive in 3rd and 4th, never in 1st or 2nd, so if the converter is slipping a lot in lowewr gears whilst trying to make it up the hill it has to be generating more heat, also the load on teh motor must be higher as it tries pulling in higher gears.

it would seem to me to be the same question as...

should I climb a slow hill in 1st and 2nd, or should I be locking it into 3rd or 4th .

It is funny you should ask this, as I was only thinking th e other day that the ideal towing 4WD would be able to start in low range going through all gears then shift into high and select the appropriate gear from there and continue on.

Originally Posted by gregausit

It may depend on the converter locking, I have only noticed what I thought may have been overdrive in 3rd and 4th, never in 1st or 2nd, so if the converter is slipping a lot in lowewr gears whilst trying to make it up the hill it has to be generating more heat, also the load on teh motor must be higher as it tries pulling in higher gears.

On a steep climb the converter will be slipping anyway. My theory is that, by using low range, you are reducing the load (and therefore heat) on the main box by sharing the torque multiplication with the transfer case.

Stephen.

Quote It is funny you should ask this, as I was only thinking th e other day that the ideal towing 4WD would be able to start in low range going through all gears then shift into high and select the appropriate gear from there and continue on.

Funny you should think that Should we look at transplanting an Eaton No4 2speed diff into it?
Cheers Scott