OT: Automatics that have done a lot of towing

I seem to recall that in the old days auto boxes used to have a dipstick and a sniff of that would tell you if the brake bands had been slipping and burning. Slushboxes are pretty reliable though and as long as it shifts okay and you don?t get any sensation of clutch slip in the drive train (revs staying higher than expected after an up change) it?s probably okay.

I?m no expert though so you might well get better advice elsewhere.

Tim

Don't really see why towing should shorten the life of an auto. Any more than a manual transmission.

Different types of auto are more prevalent these days, it is a slushbox, a dual clutch, or a variomatic type?

p.s. looked at wikip to see what names Merc give to their gearbox types, didn't realise some of them have two reverse speeds

"Six-speed manual gearboxes from the C Class and SLK are standard on the E200K, E220 CDI and E270 CDI, with the option of MB's excellent 'Tipfunction' 5-speed auto. "

"The transmission oil cooler of automatics is sited in the radiator matrix, so failure can lead to coolant entering the transmission and destroying it, leaving the owner with a bill of £4k +. Apparently this fault occurred in cars manufactured between 2000 - 2003 and only when a Valeo radiator is fitted. Two other well known faults which might cause expensive damage are failure of the oil seals to the wiring looms from the top of the cam cover and to the autobox which is electrically operated."

I can't see anything that would be affected by towing - the engine has probably run slightly harder, but these are big engines and are likely designed for it. I can't imagine this one has got near the top speed of

Theo

In article , Mike McLeod writes

Could it be to do with the fact that long ago autos for towing were fitted with an optional oil cooler?

I don't know either. I wonder if the fact that they were normally 3 speed has something to do with it.

You might get wear caused by more frequent gear changing particularly when going up a hill.

It's a 2003 car so likely an MB made slushbox. BMW don't make their own boxes so tend to try out the new types early on. MB are (or were) more conservative since they make their own.

Most autos on larger engined cars have a transmission oil cooler. A larger one may be needed for heavy towing. I'd hope that would have been done at the same times as fitting the tow bar and heavy duty rear suspension, if needed.

Is a modern car of that age a good idea, no matter what the model though? Brian

We towed a caravan for ten years and quite a few tens of thousands of miles across 4 makes of unmodified car all with auto gearboxes and never had an issue. Scotland, Wales, West country ... all the long uphill drags you can think off.

I suspect as with most things, it's not the car. It's the driver ....

You'd normally lock it in a suitable low gear manually for ascending or descending a serious hill. Same as you'd do with a manual?

It's 17 years old, with lower than usual average mileage.

Get it it cheap enough with a new MOT and it could be a bargain.

Andrew

We're talking ancient history here though. My first 4 speed auto was an Austin 1100.

In article , "Dave Plowman (News)" writes

Pretty standard in the sort of time frame we are talking here. This goes way back. 1970s ish.

NT

The first autos in the UK were fitted to Rolls. They were four speed too.

Do buck up. Rolls change from a 4 speed fluid flywheel box to a 3 speed torque convertor one in the 60s. The early 4 speed box had a poor choice of ratios - due to its design.