Thread: Heat, towing and the ZF Auto

What sort of weight & what sort of terrain will you be driving through?

If a couple of tonne & not over mountains, then you'll be fine. I'd drop back to 3rd unless it's doing it really easy in 4th.

I expect it will be a tad over two ton, whatever a 107" weighs plus about 500 kgs for the trailer. Mostly flat country on bitumen road.

How long since the auto fluid's been changed??

We pull a 20 foot tandem van (2.5 tonnes) behind our 4.6 litre D2 V8 with the standard ZF4 22 auto transmission, but always in third at around 85-90 kph. 4th is just not practical, since even with the 4.6 litre, it can't hold speed except on the smoothest freeway, and then only above 100 kph which is too fast. We tow up to around 500 km a day, and have done so in over 30 degree temperatures, including hills etc, but we do stop for 30 minutes or so every two hours for a coffee break. We have had no problems to date (touch wood).

For safe measure I would, and did, flush and run a full synthetic in the box. I have the same - Td5, auto '03 towing over 2t car to the track, a few hundred k's with no problems at all. In 4th gear all the way also. I found I could do 90k/h no problems and 100 was easy too. 110 though and you just know she's sucking the juice. so I stuck to just under 100...

Originally Posted by Grumndriva

We pull a 20 foot tandem van (2.5 tonnes) behind our 4.6 litre D2 V8 with the standard ZF4 22 auto transmission, but always in third at around 85-90 kph. 4th is just not practical, since even with the 4.6 litre, it can't hold speed except on the smoothest freeway, and then only above 100 kph which is too fast. We tow up to around 500 km a day, and have done so in over 30 degree temperatures, including hills etc, but we do stop for 30 minutes or so every two hours for a coffee break. We have had no problems to date (touch wood).

Pedro, the point is that the transmission doesn't know what engine is in front of it, and if it will handle our (upgraded) engine's torque pulling a heavier and bulkier load, then it should probably also handle his task.

Thanks guys,

My greatest concern is that if allowed to slip in 4th it will cook the ATF. The engine in this situation does have bearing on it, if your engine can provide the umph to get it to lock up in 4th vs something that can't hold it in 4th then what is in front of the auto will have some bearing.