BMW M3 E92 BMW Performance Steering Wheel

[pony]

I know someone who fitted temp sensors to gearbox and diff on an S50 converted E30 (sensors were in place of the drain plugs from memory). He was telling me that its very surprising just how long the gearbox and diff oil takes to warm up under normal driving conditions.

Assuming engine oil takes 15 minutes .... How long did they take ?

Depends on how the car is driven.

For example, diff oil will heat up quicker if the car is driven at high speed.

Just normal town driving but no stuck in traffic jams like rush hour.
How long would it take under those conditions ? I think sport Evo had temp gauges to measure diff temp and gearbox temp.

I have noticed oil temp takes roughly 15 minutes .... Though all the rev counter lights extinguish about 5 minutes earlier. On motorway never really reaches the middle. Will do with town driving if you start giving it some .... Presumably because less air flow.

Water temp takes about 5 minutes to get to right temperture.

In general I hear the warm up us very critical with these engines + regular oil changes .... So the way I warm it up is only rev to 3000 rpm till oil warmed up ....

Is there a specific warm down procedure with these engines ?

[harry_p]

no wonder it's taking 15 minutes for the oil to warm up if you're not going over 3000rpm.

jesus, there's taking care and there's driving like an old woman...

the general rule is drive gently until the gauge starts to move off its stop, than progressively increase revs and load, without being silly, until it's up to 'normal' operating range. then give it death.

gearbox and diff oils arent so temperature critical as they have an easier life, there's a nice big bath of it that the gears splash around in, although it's still worth not thrashing a car until theyve had a chance to warm through. temperature gauges are usually only fitted to cars taken outside of their normal use, i.e heavily modified or lots of track use, to make sure the oil isn't getting too hot, not to make sure it's warmed up properly before use.

you could be as carefull as you like with the warm up procedure but unless you've owned the car from new you have no idea how it's been treated for the previous 6+ years of it's life.

there's a difference between sensible and being poinlessly over protective.


Warm down procedure?

not really, just drive normally for the last half mile of a journey so the manifolds and brakes aren't glowing red hot when you park it and it'll be fine. it's only really turbos which need to warm down as their turbos glow red hot and have oilways through them. if you thrash it then park up the oil sits in the turbo and boils up and leaves deposits which means the surfaces are dry at the next startup, and are gradually clogged up.

[bss325i]

I think sport Evo had temp gauges to measure diff temp and gearbox temp

Nope, that's an alpina thing, they did LCD aux displays for e28, e30, e34, e36 which included engine oil temp, pressure, diff oil temp and on some manifold vacuum.