Ian B Walker
MB Enthusiast
- Joined
- Jun 7, 2003
- Messages
- 7,668
- Location
- Freckleton
- Car
- 300-24, saloon and coupe, E300 24 valve diesel estate
depends on if you checked out the original box when it was good, took stats and are now comparing like for like. Good luck with Dronsfields if its wrong 
Dieselman
Banned
- Joined
- Jul 13, 2003
- Messages
- 34,198
- Car
- Peugeot 403 Convertible
Obviously something is not right but it could be as simple as the speedo drive gear being for another car.
You really should've checked the box designation before fitting.
You really should've checked the box designation before fitting.
panason1c
MB Enthusiast
oscar55 said:i have just had a gearbox fitted to replace mine after 420.,000 and the revs at 80mph seem higher than before at 3000 anyone tell me if this is nomal for a 300d 1991 or is it the wrong box? its under warrenty from dronsfields
All gearbox's have the same top gear ratio of 1:1 ..so, as previously mentioned, it is probably the speedo drive ratio that is different.
Just be aware that you may now be travelling at a faster speed than is indicated by the speedometer!
BTW...Speeding is an 'absolute offence' which means that regardless of the reasons for speeding (such as a faulty speedo!) you will always be found guilty unless you can PROVE that you were NOT speeding
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grober
MB Master
If Dronsfields can give you the chassis no of the car the gearbox was from, you can check what the final diff ratio was with MB and compare it with yours. that way you should know for certain. Unfortunately its doubtful Dronsfields will have that info or be willing to get it for you. You would be surprised just how many systems in the car use that road speed as an input parameter for the efficient running of the car, but if its running OK then fine, apart from the speedo accuracy from a legal point of view as has been mentioned.
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panason1c
MB Enthusiast
It might be possible to swap the speedo drive gears from your original box to the new one without too much difficulty?...perhaps someone more mechanically familiar with your type of box could comment.
The easiest way to check the accuracy of the speedo is to follow a friend in his car at pre-arranged speeds...as a temporary solution you might then want to mark your speedo at 30, 40, etc with the small stickers that motorcyclists use to mark their imported bike speedo's that are in Kilometers. You can get them from m/bike shops.
The easiest way to check the accuracy of the speedo is to follow a friend in his car at pre-arranged speeds...as a temporary solution you might then want to mark your speedo at 30, 40, etc with the small stickers that motorcyclists use to mark their imported bike speedo's that are in Kilometers. You can get them from m/bike shops.
panason1c said:
Or borrow a portable gps satnav that displays current speed.
