does downshifting manually hurt the tranny?
does downshifting manually hurt the tranny? 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.
Yrs ago I heard it did, but wasn't sure if it really did.
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.
Going from overdrive to drive is ok, but not down from there! This is from Don Stanley at TSI Racing. http://tsiracing.com
Last edited by libertyforall1776; Jul 13, 2014 at 07:59 AM.
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 .
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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
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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.
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.
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From: Wichita KS / Rancho San Diego
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.
I'm pretty sure that MVB cars aren't supposed to be down shifted until the car comes to a stop.
That sounds like a pain in the *** to have to come to a complete stop every time you want to downshift a gear...
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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.
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...
That sounds like a pain in the *** to have to come to a complete stop every time you want to downshift a gear...
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.
My dad had an old MR2 back in the day he down shifted from 4th to 2nd on accident when he was doing 80mph.
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.
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.
Last edited by AnotherWs6; Jul 14, 2014 at 12:49 PM.
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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.