06blackGTO

iTrader: (20)

Just wondering, say when your slowing down like coming down a ramp, does it hurt to manually downshift the tranny? just to help slow it down? just lightly.

Yrs ago I heard it did, but wasn't sure if it really did.

redtan

iTrader: (5)

I've been trying to figure this out also. I recall an old post from Frank at Performabuilt saying it's ok to do so as long as you give the engine some throttle, but doing it without any throttle input will mess up some parts really quickly. Hopefully he or someone else can chime in about this more.

01ssreda4

iTrader: (96)

I think its fine, as long as you arent acting like its an M6 trying to road race there should be no appreciable damage done.

Monzsta

The problem is you're relying on the little overrun clutches to apply and hold. It tends to wear them pretty fast.

libertyforall1776

iTrader: (2)

Going from overdrive to drive is ok, but not down from there! This is from Don Stanley at TSI Racing. http://tsiracing.com

06blackGTO

iTrader: (20)

Ok. Thanks. I won't be doing it then. I don't need to be screwing up my tranny.

performabuilt

iTrader: (25)

I do not feel it causes any real issues other than if you have the set up to allow downshift to 1st at any speed you could overunn some trans internal parts to excessive RPM and or the ENGINE .

redtan

iTrader: (5)

So besides keeping an eye on RPM and not dropping down to a gear at the wrong speed, there's nothing else that we have to worry about in terms of damaging or shortening the life of the transmission? Is this only the case in built transmissons or can stock ones handle it too?

JustAFooL

iTrader: (45)

This is my belief. An automatic trans is intended to do just that, shift on its own. I'm not saying it is overly hard on parts, but it's not what it's meant to do either. If you want to change gears, get an m6.

redtan

iTrader: (5)

I gotta ask another question tho...if this is so bad for the tranny then what do people with full manual valvebodies do? Replace their units every 2-3000 miles?

JustAFooL

iTrader: (45)

I'm pretty sure that MVB cars aren't supposed to be down shifted until the car comes to a stop. Seems like I've heard something will free spin inside the Trans if you downshift.. Then again I could be completely wrong.

RevGTO

iTrader: (12)

What is the difference if the computer commands the downshift based on VSS & TPS or if you command it? As long as you rev match and don't over rev it, I don't see what the problem would be. I do it from time to time when I feel like it.

redtan

iTrader: (5)

Say you're doing 70 on the highway and want to downshift a gear to pass someone or go up a long hill? Does that mean they have to pull over to the shoulder, come to a complete stop and then get back up to speed but only go up to 3rd gear?

That sounds like a pain in the *** to have to come to a complete stop every time you want to downshift a gear...

"MAC"

iTrader: (1)

My dad had an old MR2 back in the day he down shifted from 4th to 2nd on accident when he was doing 80mph. He said not only did it destroy the trans but some of the clutch broke off and stuck into the fire wall and engine. If you go down one gear you should be fine but say from 6th to 2 i wouldn't be doing that.

JustAFooL

iTrader: (45)

If your doing 70 on the highway with a 350/400 there would be no need to downshift if you got any *** behind it at all. I said that I remember reading a thread on here where people were stating something would free spin inside the trans.. I have no personal experience though

redtan

iTrader: (5)

Talking about 4 speeds here with OD. You would be going WOT in an overdrive 4th gear at 2000rpm?

Obviously if you put it in 2nd gear at 80mph you're going to destroy ****, just talking about regular RPM appropriate downshifts. Like for example going 50mph and instead of waiting around for the 4-2 downshift, can you put it in 2, get the RPMs up to 4k and then have the "instant" hit not having to wait for a downshift.

"MAC"

iTrader: (1)

Ahh i see well either way i wouldn't recommend down shifting unless your breaks are out

Latch

iTrader: (8)

Even if you manually downshift to 1st at 70 mph it won't actually perform the shift... the computer won't let you over rev it.

AnotherWs6

iTrader: (17)

As long as you are getting too aggressive with downshifts you should be fine. I downshift my truck - with a 460le - everyday. 275K miles later still doing just fine, tranny is still untouched. When going downhill, slowing down for sharp turns, manually dropping it in to third while towing. As long as your not going from fourth to second while doing 70..... just be reasonable.

Also had an 86 TA when I was younger with a ratchet shifter. May as well have been a manual because I purposely controlled every shift. Never had any issues.

PBA

As long as you give it throttle at the same time you backshift the lever, you can then let off the throttle to de-accelerate to use engine braking and you will not cause any problems for yourself doing it this way. The backshift happens in less than .25 second when you give it throttle at the same time. If you downshift it without giving it any throttle, you will wear out the overrun clutches in short order.