long and steep ascents and decents in auto

[disco_mitch]

in a d1 tdi auto

went away for the weekend and there were some decent stretches which were steep and long up and down, when we got to the top i jumped out and she smelt like the gearbox or something might have been a bit hot no lights on the dash and the engine temp didnt budge, had about 600kg of trailer and she struggled big time to pull it up to the top

on the way down i locked it into first and second and on the really steep long ones i used low range and the brakes only when i really had to if the auto was running away

so what do you do whats the best way to approach this is it no good for the car

[Blknight.aus]

force it down, a gear that doesnt work the TC too hard on a climb is bet.

for descending stick it in the lowest gear youve got that will hold the speed you want to do hold the engine revs up untill the vehicle is on the descent then back off the noise.

If you have it available select a mode that will lock up the TC, if you dont have it next time the box comes out for servicing get it modded so the TC can lock up in all but first gear.

[camel_landy]

For climbs, you need "The highest practical gear".
For a descent, you need "The lowest practical gear".

On the climb, the slightly higher gear will give you the much needed momentum. It will also help prevent torque spin... i.e. wheel spin. (The lower the gear, the more torque you have - Hence the higher gear). This is where an auto box comes into its own as it will automatically select the "Highest practical gear"... As long as you select 'D'. ;)

On the descent, you need to use engine breaking so manually selecting 1st Low will give you that. Thing is, on the older style auto boxes, 1st low is still quite high!

To descend with your auto 'box:


Approach the edge of the descent.
Select 1st Low.
Stick your left foot on the brake & gently raise the engine revs. (This will make the torque converter lock up)
Gently release the brake and once moving take your foot off the throttle.

The descent will still seam a little quick but at least using this method, you'll avoid that sudden lurch as you go over the edge.

HTH

M

[mike 90 RR]

got to the top i jumped out and she smelt like the gearbox or something might have been a bit hot no lights on the dash and the engine temp didnt budge, had about 600kg of trailer and she struggled big time to pull it up to the top

Then you should have had it in low range ... It will give you more revs / more torque & be kinder to the Auto



on the way down i locked it into first and second and on the really steep long ones i used low range and the brakes only when i really had to if the auto was running away

Low range / 1st ... 1 foot slightly on brake / other foot to add revs motor to move & lock up TC for engine braking on decent / don't ride the brakes

I drive with 2 feet working

Mike
:)

[disco_mitch]

i still dont quite get locking up the tourque convertor i thought this didnt happen till 75-80 i wasnt riding the brakes thats one thing i wont do i did use them sometimes but only when the auto was running away and i was coming up to a tight corner that i needed to slow down for

on the way up we were sitting on average 50kmh so low range would not have worked unless i went a lot slower it tops out at 40

[B92 8NW]

The term lock up has been used erroneously. I'm not sure if stalling it up is a better term.

[V8Landy]

I don't think he was offroad.

[mike 90 RR]

I don't think he was offroad.

:eek: Oh ... in that case .... Install a external oil cooler to the auto and change the Auto fluid

[Blknight.aus]

i still dont quite get locking up the tourque convertor i thought this didnt happen till 75-80 i wasnt riding the brakes thats one thing i wont do i did use them sometimes but only when the auto was running away and i was coming up to a tight corner that i needed to slow down for

on the way up we were sitting on average 50kmh so low range would not have worked unless i went a lot slower it tops out at 40

on road you want the TC locked for most effecient running and to stop the TC from cooking the oil.

Locking the TC is also the best thing for descending as you then have a mechanical coupling all the way through from the wheels to the pistons.

you might be confusing coupling point and Lockup which is explained on this (http://www.aulro.com/afvb/456777-post30.html) post on my Autos explained thread.

if you want som further explination feel free to ask.