Mercedes-Benz Forum banner
1 - 16 of 16 Posts

·
Registered
93 190E 2.6; 82 300 SD Turbo
Joined
·
1,689 Posts
Discussion Starter · #1 ·
What happens if your doing a speed thats past the dots on your speedo and you downshift to that gear?

Will the tranny actually do it? Is there some sort of idiot mechanism to prevent this?

What happpens?

I've always wondered..does the trans blow it self to bits? does the engine give you the finger?
 

·
Registered
1989 300SE (Rear Ended & Junked) 1995 E420, Fully Loaded with Ortho Seats & Rear Sun Shade :)
Joined
·
511 Posts
Maybe, you can experiment on behalf of us all and tell us? It'd make for a nice sticky thread :thumbsup:
 

·
Registered
'90 560 SEL RUF 42,000m, '90 560 SEL RUF 56,000m, '90 560 SEL RUF 150,000m '90 560 SEC RUF 225,000m
Joined
·
12 Posts
Tranny won't make the shift until the revs drop low enough to prevent over-revving, then it'll shift.
 

·
Registered
'90 560 SEL RUF 42,000m, '90 560 SEL RUF 56,000m, '90 560 SEL RUF 150,000m '90 560 SEC RUF 225,000m
Joined
·
12 Posts
An addition; It's how to prep for traffic light grand-prix; click tranny into 1st as you slow down, it'll take the gear as soon as it can so you've got the lowest gear possible when the lights change.
 

·
Registered
1987 420 SEL
Joined
·
2,097 Posts
Sounds like someone's going to be looking for a new transmission messing around with the shifter.
 

·
Registered
see my signature.
Joined
·
909 Posts
Did it on my W124 by accident one day.


It downshifted and bounced off the REV limiter
 

·
Registered
'90 560 SEL RUF 42,000m, '90 560 SEL RUF 56,000m, '90 560 SEL RUF 150,000m '90 560 SEC RUF 225,000m
Joined
·
12 Posts
Guys I hate to disagree with you, but I've been doing this with euro 560 trannys for 10 years and none has ever hit a limiter. They wait, they shift down. Maybe euro spec are different but i can hit a limiter on the way up by not shifting in time, but never on the way down.
 

·
SuperModerator
1986/1990 W126
Joined
·
17,684 Posts
The vague manual seems to hint that it might not select the gear you select downwards until the revs are low enough. I'm not tempted to try.. Lol..
 

·
Registered
1966 200 Diesel; 1985 500 SEL (wrecked); 1991 420 SEL; 1979 280E (Home Market); 1993 190E 2.6
Joined
·
584 Posts
A good 722.3 will put up with a lot of abuse before it decides its had enough. A worn out 722.3 will continue to go for a long time before catastrophic failure. That being said there is no reason to find out the limits of the design.

-Wolf
 

·
Registered
1983 500 SEC Lorinser 1971 280se w108
Joined
·
1,963 Posts
Guys I hate to disagree with you, but I've been doing this with euro 560 trannys for 10 years and none has ever hit a limiter. They wait, they shift down. Maybe euro spec are different but i can hit a limiter on the way up by not shifting in time, but never on the way down.
Ive over zealously changed down on the motorway while flooring it and hit the rev limiter

OT I was driving in a 99 ford falcon once with the cruise on and debating with a passenger what would happen if I shifted into neutral with the cruise on
I assumed it would just cancel out the cruise but no car just reved up to the limiter !
 

·
Registered
'90 560 SEL RUF 42,000m, '90 560 SEL RUF 56,000m, '90 560 SEL RUF 150,000m '90 560 SEC RUF 225,000m
Joined
·
12 Posts
Ive over zealously changed down on the motorway while flooring it and hit the rev limiter

Yep. You floor it, it'll take the gear and pretty much immediately hit the limiter and remained pinned in the gear 'cos it can't change up. but it'll never downshift until the revs are low enough to allow it to do so. No exploding trannys or valves bouncing.
 

·
Registered
'90 560 SEL RUF 42,000m, '90 560 SEL RUF 56,000m, '90 560 SEL RUF 150,000m '90 560 SEC RUF 225,000m
Joined
·
12 Posts
um wrong? If your statements true then why would shifting from 5th to 1st blow up a transmission
It will blow up a transmission. It won't blow up all transmissions. Shift a stick shift into first at highway speeds and it'll lock wheels (or at least drastically slow them) and bend valves, but it won't blow up (seen a lot of race cars with road trannys do this). Shift some autos into first and the tranny blows up, some just wait. Shift a paddle-shift manual down and it'll just ignore you.

But if you down-shift my 126's down they wait, then take the gear. (I'm not saying every 126 does this, but the ones i have do. (I actually went and did this to check since my first post. The tranny waited, then shifted down when the reves dropped).
 

·
Premium Member
560SEC, 190E, Frontier, 240Z
Joined
·
1,334 Posts
My Dad was teaching me to drive in his old 280SE, we were driving about 20mph.

He said: "Park right here"

So I put the tranny into Park.... KLAK~KLAK~KLAK~KLAK--ooops! sorry Dad.
I was 15, not so smart.

Never seemed to bother the tranny for all the years we owned it later.
 

·
SuperModerator
1986/1990 W126
Joined
·
17,684 Posts
My Dad was teaching me to drive in his old 280SE, we were driving about 20mph.

He said: "Park right here"

So I put the tranny into Park.... KLAK~KLAK~KLAK~KLAK--ooops! sorry Dad.
I was 15, not so smart.

Never seemed to bother the tranny for all the years we owned it later.
Ouch :) I was letting a friend drive my non MB automatic once, (a Fiat) and he popped it into park at about 30mph. I laughed afterwards but not at the time... Worked fine afterwards.
 
1 - 16 of 16 Posts
Top