I remember some people saying that they do WOTs on a 65 mph highway...well today I was tried doing a WOT...I followed the steps: downshift to 2nd etc. My car was above 90 mph, the rpm <5500 and climbing. I let off the gas before red zone because I ran out of highway. My question is: How did you guys complete the WOT exercise within 75 mph.:confused:

you needed to drop the tranny into 2nd

Correct, if you were going 90 you were in third... The ECU is smart enough not to down shift if it will over rev the motor...

you needed to drop the tranny into 2nd

OK I think I missed something...how do you do that

put the shifter into 2nd...?

The best way is to start out in second from a standing start. Nail it and run it up to 60-70, then let it back down to 50. Put it in "D". Mission accomplished. You could also start out in "D" and nail it. Let it wind out and give you a full throttle shift at 6000-6500 RPM (depending on the engine), and then back off, all before reaching 55 MPH.

you needed to drop the tranny into 2nd

:wtf: I haven't been on here for a while. Is this the advice people are giving out? Manually downshifting an auto tranny is one of the worst things you can do.

If you really want to hold a gear, blip the throttle so that the tranny builds line pressure, then downshifts on its own when it's reached enough pressure to complete the shift with minimal stress to the clutches, then move the shifter to that gear.


As for the WOT maintenace, just drive the car. Bring the revs up once in a while and you'll be okay.

you put the tranny into 2nd gear and then you lauch it i never said speed up then put it into 2nd gear, dont get critical with my advice when you have no idea what it ment...

you put the tranny into 2nd gear and then you lauch it i never said speed up then put it into 2nd gear, dont get critical with my advice when you have no idea what it ment...


Well the OP was talking about doing 65mph, then you said to "drop the tranny into 2nd". It was not clear whether to do this while doing 65 or while stoped. Someone may have miinterpreted that. :shrug:

w/e anyone with common sence should of assumed i ment from the start b/c as you said and as i know droping it down like that is horrid on a tranny

BTW. Our trannys will not down shift if it over revs the motor... the call for second gear is ignored untill the motor (and the car) slows down on its own...

Shifting into 2nd at 65 causes nothing to happen.
BUT I still wouldn't do it!

I wouldn't dare it either .Even though I don't think there would be nothing serious to tranny . Only times I shifted in 2 manually when there is a downhill as a result of relieving the brakes at that stage .

....
I My question is: How did you guys complete the WOT exercise within 75 mph.:confused:

Several points to keep in mind when you are practising this beneficial procedure; leave the gear selector in "2" and do not rev the engine to the RPM at which the PCM will force a shift to third gear.

This is what I have been doing about once per month for more than 5 years; pick a safe time and place to slow to about 50 MPH, place gear selector in 2, go WOT to just short of 6,000 RPM, let off gas feed, let engine brake the car back to 50 MPH, repeat.

What is happening? WOT in 2nd gear from 50 MPH puts a good load on the engine and compression pressure reaches a high level. The positive pressure puts a load on the piston rings in one direction. Closing the throttle valve at the end of the run creates maximum negative pressure (vacuum) putting a load on the piston rings in the opposite direction. Repeated WOT acceleration followed by compression braking applies alternating positive pressure and negative pressure on the piston rings. This tends to keep the rings free to move in the lands and removes carbon buildup.

If you see a cloud in the mirror during the WOT portion, you are seeing carbon being forced out of the combustion chamber. Do it again.

Works for me.

... If you're going 65 and you floor it, what do you think it does? It downshifts into second. If you stick the shifter in second, what do you think it does? Yeah, it downshifts into second. Either way it will not downshift into 2nd until it's ready.

At 65, it will drop from OD into D. I don't think it will down shift into 2nd at 65, but I would not swear to it. The owners manual has the max (do not) downshift speeds in it. Not sure, but I would guess that those are where the downshift lockout speeds are.

... If you're going 65 and you floor it, what do you think it does? It downshifts into second. If you stick the shifter in second, what do you think it does? Yeah, it downshifts into second. Either way it will not downshift into 2nd until it's ready.

As ranger points out... This not exactly the way it works... All of the forward shifting that these cars do is controlled by 2 solenoids..

Those 2 solenoids are controlled by the ECM/PCM... And the PCM on these cars is very smart...

Take out a stone cold engine and attempt a WOT and the PCM thinks... "ouch" and shifts well early of the 6500 red line...

Leave the tranny in first and push the car to red line and the PCM thinks... "he's not paying attention" and shifts into second.. and then third and then drive...

Pull the gear selector into 2 at 65 MPH... The PCM thinks... "That's nuts...I'll consider this in a moment" and it ignores you... until it thinks that it safe for the power-train to attempt...

Its kinda like having a little GM liability lawyer riding along in the tranny...

At 65, it will drop from OD into D. I don't think it will down shift into 2nd at 65, but I would not swear to it. The owners manual has the max (do not) downshift speeds in it. Not sure, but I would guess that those are where the downshift lockout speeds are.


It will in fact drop into 2nd at 65, and even 70 plus!, I do it often with no problems, it will then accelerate to 85 before changing to 3rd.
At least it does in the STS, don't know about the SLS or DHS, maybe they are programmed differently.

:wtf: I haven't been on here for a while. Is this the advice people are giving out? Manually downshifting an auto tranny is one of the worst things you can do.


I just read this and had to comment. I'm not even gonna get into the whole WOT "maneuver" but this just stuck out for some reason.

Do you even know how an automatic transmission operates? I suspect that you have no idea, or at least don't fully understand it judging by what you said. Figured maybe I'd just clear it up for you. Manually downshifting an Automatic transmission has absolutely no negative affects. It is no different than putting your foot to the floor and having it downshift on it's own. If anything, there's less stress on the, since the clutch packs are not engaging under a high load (I assume you know what a clutch pack is when I say this). If manually downshifting an auto tranny were really as bad as you say it is, do you really think all those big car makers out there would be designing this feature into every vehicle knowing full well how much damage it's doing? I kinda doubt it.


Also, to clear another common misconception, the harder and quicker the shift, the longer the tranny will last. Auto manufacturers design the shift speed to be on the slower side to keep the shifts smooth. Some (well, pretty much everyone these days) use Pulse Width Modulation to gradually apply the clutches to slowly engage each gear, keeping the shift smooth. This means that the friction disc slip against the steel plates as the clutch pack is engaged. Rasing the fluid pressure, and the the fill rate of the clutches means a firmer more precise shift with less slippage, equaling longer clutch life. Unfortunately this tends to "shock" the rest of the drive train which is where you end up with problems.



That is all....

It will in fact drop into 2nd at 65, and even 70 plus!, I do it often with no problems, it will then accelerate to 85 before changing to 3rd.
At least it does in the STS, don't know about the SLS or DHS, maybe they are programmed differently.


You are correct. In the STS, 2nd gear runs otu at about 85mph +- 2-3mph. It'll downshift into second anywhere near around 70-75mph or below, since there's no danger of over-revving the engine at that point. It'll also downshift into 1st around 35mph as well.

Shifting into 2nd at 65 causes nothing to happen.
BUT I still wouldn't do it!


What do you think happens when you put your foot to the floor at 65mph. The car downshifts into 2nd gear anyway, regardless of whether you manually selected it or not.

To me, this is the best feature of the STS! Nothing like cruising about 70 and needing to pass.. It downshifts to second and GOES!!

Any of these cars will downshift into 2nd at 65. The STS/ETC/DTS/Concours will, and the others have a lower final drive ratio (even though they have a lower redline) so they'll downshift too.

As ranger points out... This not exactly the way it works... All of the forward shifting that these cars do is controlled by 2 solenoids..

Those 2 solenoids are controlled by the ECM/PCM... And the PCM on these cars is very smart...

Take out a stone cold engine and attempt a WOT and the PCM thinks... "ouch" and shifts well early of the 6500 red line...

Leave the tranny in first and push the car to red line and the PCM thinks... "he's not paying attention" and shifts into second.. and then third and then drive...

Pull the gear selector into 2 at 65 MPH... The PCM thinks... "That's nuts...I'll consider this in a moment" and it ignores you... until it thinks that it safe for the power-train to attempt...

Its kinda like having a little GM liability lawyer riding along in the tranny...

Hey, before you go off trying to correct me, try reading what I'm typing. I said 'it will downshift when it's ready' and then you tell me I'm wrong and type 6 paragraphs saying that it will downshift when it's ready. :bigroll: