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All you auto drivers… I’ve got some auto trans questions for you all.

Does anyone here downshift when slowing down?

As in, foot on brake, put it in 3, then 2 on the auto shifter.

Does this cause strain on the box/gears?

Does this cause more heat?

For those of you with the upgraded valve body in their auto box…

If it’s in drive, I hear that the up-shift speed/feel depends on how much gas you are giving it.

So if just cruising along, the shifts are nice and smooth and if you are getting up it, the shifts are hard and fast.

Does it effect the shift at all if you were to say use the gear to slow down the car and say you have it in 2 while in the corner and you plant it, the revs go up and you just slip it in D while still gassing it… does it still shift like it should or does this confuse things for the ecu and it’s shift points?

What if any aftermarket trans coolers are you lot using?

Where is it mounted?

What did it cost?

Is it a DIY kinda job?

Anyone got a DIY gearbox oil change instructions or is it best to just buy your oil and take it to a shop who has a hoist and pump?

Anyone using Castrol gearbox oil? Which one?

How many litres?

Cheers

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the point of an auto is to save you having to change gears, so i dont like to play around with it, but -

i have noticed that yes, just cruising along you dont feel or hear the gears shift, or even feel any diference in power. it just cruises and cycles through them.

if you gun it of the line, then yeah it changes very solidly. It hits 6750 and changes with a very hard feel into 2nd. No noise, its a relatively smooth transition, you just feel the power drop for a split second, then the revs drop, and bam youre in2nd and forced to the back of your seat again.

theres no point holding out to change it into 3rd, cos itll change at the same place anyway. If you wait for it to get to just under 7k, then slip it into third, you'll bounce off the limiter for a little bit. It takes a few seconds for it to change after you change gears.

Same as when you go from park to reverse, or reverse to 1st, it takes a split second.

i downshift manually sometimes GTST... but only at low speeds...

trans cooler was an item from supercheap for $100ish. its mounted on the drivers side of the front bar, in a mirrored position to the stock intercooler.. works well i think :D definately a DIY job.. very easy to install in about 2 or 3 hrs

as for gearbox services, i always take it to a mechanic..

will be able to comment on shift kits in a couple of weeks when my high-stall converter and stage 2 shift kit arrives :no::D

my trans cooler is sitting where the standard cooler was. there is group buy on with the davies craig auto cooler kits, its not really a group buy, its just offered at a reduced price of $118 with everything you'll need. i didnt like the way they suggested to mount them so i made up my own style, i'll post some pics tomorrow. and it is a DIY job.

i do downshift when stopping, and i do drop it into 2nd when cruising at 60 to feel some G's. i have been for 2yrs and my box doesnt slip or anything.

i used castrol dextron III with my oil change.

i'll be posting up a "how to" on changing oil and cleaning the filter inside the auto's (r33) so look out for it.

autos are great for drag racing, provided they can handle the power. Quick shifts, and if you have a trans lock (engages reverse and first at the same time, then releases reverse when you launch), you can get some crazy launches off the line.

If i need to brake in a hurry, ill shift down. If im going up hills, ill leave it in 2nd sometimes so it isnt constantly swapping cogs.

There are merits for downshifting (youll save your brakes, tighter around corners cos you arent just freewheeling etc) but theres no point reviving it out then clicking 2nd, then 3rd, then engaging O.D. The computer shifts at peak points anyway.

Does anyone here downshift when slowing down?

As in, foot on brake, put it in 3, then 2 on the auto shifter.

Does this cause strain on the box/gears?

Does this cause more heat?

For the several weeks that I was in full automatic mode with the shift kit (upgraded valve body) I frequently utilised the engine break to mainly go around corners.

Constant gear changes will generate more heat but, proper service at appropriate intervals, good ATF & ATF cooler the trans should last longer & delay the inevitable.

For those of you with the upgraded valve body in their auto box…

If it’s in drive, I hear that the up-shift speed/feel depends on how much gas you are giving it.

So if just cruising along, the shifts are nice and smooth and if you are getting up it, the shifts are hard and fast.

Yeah thats pretty much right. The upshifts aren't harsh (except 1st to 2nd gear change when driving off slowly from idle) whether on the gas or cruising but, you do feel more push back into the seat at full throttle compared to stock.
Does it effect the shift at all if you were to say use the gear to slow down the car and say you have it in 2 while in the corner and you plant it, the revs go up and you just slip it in D while still gassing it… does it still shift like it should or does this confuse things for the ecu and it’s shift points?
To begin with the auto ECU isn't always predicatble especially depending how far you got the pedal down when in D, coz things can get hairy when cornering in 3rd (or O/D) & it decides to kick down a gear :laugh:. But, normally if foot is firmly planted in 2nd & then up-shift it will go into & stay in 3rd.

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