If you do that, I'd worry about heat building up in the tranny. Your gas mileage will be worse too because the engine is needlsy spinning at a higher RPM. Which also leads to wear on the engine from spinning at unneccisary RPMs. I guess you could drive like that if you needed a brake job and were putting it off for as long as possible.

 

The electronically controlled 4L60E is pretty good at shifting properly, I've found. Yeah, it's no human controlled M6, but autos have come a long way with the advent of computer rather than vacuum/cable control. There's no real point to downshifting manually in average use unless you want to engine brake or are going up steep hills that need more torque and want to lock it out of OD.

Another thing is that keeping it in second doesn't let the converter lock up (which won't lock up unless you're in third gear, which in normal driving patterns is around 30 MPH).

 

i can get .2 more out of my car in the 1/8 mile by powershifting compared to granny shifting my M6. i havent seen any negative effects. ive been powershifting varius t5s, tremecs and t56s for over 10 years and have never broken a trans. but i never miss a gear either. i dont powershift if im not at the track tho.

 

Brakes are cheaper than transmissions. If you can pick which components you want to wear more quickly, pick the cheaper one.

 

Not trying to be an a$$,but....

AronZ28: heat build-up is why trans coolers were made. I think you are misunderstanding me. In stop and go bumper to bumper in D1 the trans very rarely shifts up to third,and when it does it is usually time to step on the brake to slow down. I'm not talking driving 30mph up,I'm talking up to MAYBE 25mph.

kefkafloyd: If what your telling me is true,then WHY would you even have to downshift for long hills,the computer should not let the trans upshift under torque,right? Plus I'm talking city driving here not open road. As I said earlier I've found that the trans doesn't downshift out of 4th as quickly as (at leastfor me)it should and when it upshifts in to OD in town it's like the renouned skipshift in the Vette,just no power there if you need it.

nateh: I've been driving for a good many years and I've never had a trans go out from engine braking. If the trans can handle high rpm upshifts then it should be able to handle downshifts as well. People tend to just get lasy and think that just because it's an automatic they only have to put the car in drive (OD) and that is all,and for the most pat in everyday driving that will do,but then WHY even put thoughs gears on the selector just put "Forward & Backward,with Park" in the middle. I say the car has gears use them when needed and appropriate.

I'm not trying to change anyones driving habits here just saying this is how I use my Autotrans,and I've never had a problem with any of my cars by doing so.

 

tell me how your rear, trans, and especially trans mount look after 30k miles of constant brutal manual trans powershifting in constant daily driving... But thats whats expected..

 

I've never raced in OD, so much easier to just shift by yourself...I get alot better times in the 1/4 by powershifting. Especially since OD is NEVER needed in the 1/4. top out 1st, top out 2nd, maybe 5000 in 3rd and then throw it in OD to slow down and get on the pit road.

My brother has done the same thing with his th-350 for 3 years now and is yet to have a problem. I leave it in OD on the interstate unless a car pulls up and wants to have some fun, then i knock it back down to 3 and go full throttle.

Just my thoughts,
Dave

 

It's a fact that excessive engine braking in lower gears with the 4L60E will result in wasted clutches. An old TH 350 or 400, you could beat to death. The 4L60E is not so forgiving. There are lots of people this has happened to.

 

If it's not downshifting fast enough, you're not putting enough pedal to the metal ;p The tranny, in a certain speed range, will keep the car in third gear so long as you have enough throttle before a certain point and until a certain MPH (I believe it forces a shift into OD somewhere around the 110MPH range?). I've experimented with this - once the computer automatically downshifts, so long as you hold the pedal in that position or do not go below a certain throttle threshold (IE the computer can see that you're going back to low torque requirements), it will stay there. However, you would downshift anyway just to prevent the possibility of the OD kicking in. You can program these sorts of parameters with a programmer, and a shift kit also helps. The tow-haul mode on most trucks, for example, is a quick and dirty way to use programmability to help trannies shift properly under circumstances that require more torque rather than high speeds.

I'm not saying what you're doing will harm the tranny, the difference is probably minimal. I just don't see a point most of the time to downshift manually (and there are only two times I do, and I've mentioned them above). Coincidentally, this is also what the majority of drivers do.

Most of the time, the computer shifts better than you. The only time you really need engine braking is to keep your brakes from heating up too much (which would be coming down a steep hill and you're trying to obey hte speed limit or coming off of the highway). In town? The benefits are minimal, and there isn't much risk of overheating the brakes. Just drive the car normally unless you really need to engine brake, it's better for you and for the car.

 

You are not describing a "downshift" here. I'll try to give an example: Next time your on the road and you are up to speed(say 35-40mph)and you are comming to a stop see how long it takes for the trans to DOWNshift to 3rd and how much brake you have to use. Then try just using drive and take your foot off the thottle and see how much sooner you slow down using less brake. You can argue fuel mileage ,but at 35-40mph OD has probably JUST kicked in so were is the savings,not to mention the "extra wear and tear"on the trans making shifts for short periods up and down. Remember I an talking City street driving not highway.

Plus I think we Hi-jacked this tread,and I applogize.

 

Shoebox I have been under the impression that the 4L60E was tuffer than the TH700R. What your saying is it can't handle this type of driving? I know GM had probs with the early 700's ,but the later ones have less problems,but (knock on wood)my 700 has not givin' me one bit of trouble. I have added a shift kit,an OD kickdown valve,and a cooler,and a poly trans mount and the cobination seems to work quite well. So maybe everything that I've heard about the L60 being superior isn't nessarly the truth.

Again sorry for the hi-jack.

 

I've never driven a third gen with the 700R4, and I don't know its quirks, so I guess you can drive it any way you want. But if you are shifting the electronically controlled 4l60e yourself, I'll have to smack you around.

I know what you are talking about with keeping it in D instead of OD in town. On my old car I would do that because it didn't have much power around 40 mph when it shifted into overdrive.

 

We did. However, what I did describe is a downshift - a downshift is any time the tranny goes from a higher gear to a lower one. Whether it occurs from slowing down or speeding up is inconsequential. PLus, OD on the 4L60E doesn't kick in until 45MPH (and will come off at 40 MPH).

In town... there's not enough space where you'd be just slowing down without using brakes anyway. In the end, you'll still have to replace your brakes and rebuild the tranny at some point. Whatever floats your boat, but I feel it's just a placebo effect for you.

Have you considered installing a shift kit in your car? It really does make a huge difference (I love my Transgo!).

 

Actually... I've probably heard about 5 or 10 names for both manually shifting an automatic and clutchless shifting. I've also heard both refered to has powershifting. I guess I should have used a more accepted term. But thats what he was calling it....

Anyway, as far as REAL powershifting goes, you all suck! I spent 2 years looking for a M6 and finally gave up and bought an A4. but in all my previous cars, I never completely powershifted on the track, I did all the time in daily driving, because I could shift slow enough to time it. But doing that on the track will fry your syncro's. What I did do was tap the clutch just barely past the free travel point right as the shifter was going in to the next gear. Timing is critical. I would let off the throttle about 1/2 in first gear and probably about 1/4 in the others. That seemed to work quite well for me.

P.S.
http://web.camaross.com/forums/showthread.php?t=334891
See, I told you people refer to manually shifting an a4 refer to it as power shifting.... Don't shoot the messanger.

 

LOL, don't get sucked in. Sounds like someone else did not know what they were talking about and decided to create a new meaning for the term.