Thread: D2 TD5 Auto Use eg Towing

Hi Gavin
The slippage ( for want of a better word )you refer to is all taking place in the torque converter, sort of like 2 fans facing each other but with fluid instead of air , so no slipping clutches , but if towing a heavy load while out of lock up you are generating a lot of heat (the by product of wasted energy in the torque converter) , which can damage the clutches in the trans if too hot.

Light throttle 70 kph is fine if you can manually lock it up, you could also for now get it to lock up in 4th above 80 then ease back down to 70 by keeping enough throttle on so it stays locked up, you won't damage anything ( except for the voice boxes of the drivers behind:-)


Egt will be well and truly safe at those levels , wouldn't stress even hitting 700 for a few seconds

My comment on 1 & 2 only based on my understanding:

1. The slippage or the smoothness of changes are a consequence of the torque converter out of lock up, the damage may occur when heavy towing out of lock up due to excessive heat generated over time in the fluid by the torque converter.

2. Damage may occur if you are changing gears while still in lock up due to shock loading of the clutches.

Nick

Thanks - makes sense, and just as well I have extra cooling capacity for my ATF - its never gone above 85.

Going up to 80 then easing back to 70 is not an option unless you like $100 contributions to the Police - this is mainly on west coast highway where there is often a presence.

Have hit 700 a few times inadvertently and once panicked at 770 - inattention climbing the big hill ex Melbourne en route to Ballarat on a 45 degree day towing a camper trailer.

You need to lower the 4th lockup point.
8 words and a million dollars
towing at 2600 is way past where your TD5 makes its torque,

The more weight, the taller the tyres, the bigger the chip(or V8) the harder it is to get our auto's to lock up. The standard TD5 is pretty woefull in that regard.

nothing wrong with towing in 4th,
as I've said previously, I'd rather it lug in 4th down to around 1900rpm (that's why I built it the way it is) than "Sport" change downs occurring under full load into a non locked-up 3rd.

Put the van on, get it up to around 95 and "Heavy Auto Lockup"- it into 4th, keep yours eyes on your egts and away you go

Have you thought about changing centre diff ratio's,,
1.411 from a defender TD5
just think'in--


late edit, was just trawling through Ashcrofts site and they actually recommend this ratio for Disco towing,,
great minds huh,,

An Auto mechanic recommended that when taking off, treat it like a manual. Start in 1st, and manually shift through 2nd & 3rd. He also recommended cruising in 3rd (haven't tried 3s - is the ration different?), but I've found 4th just as good for cruising.

Towing 2T up hills is rather heavy going though - EGTs climb fast.