W123 differentials.

[DVF]

Does anybody know the rear diff ratio of a W123 diesel?

Also, will it swap straight into a petrol 280 auto?

Has anyone tried this before?

What I'm trying to do is find a way to get the engine speed down on the motorway (over 3000rpm at 60mph is not fun), and this seems like a good idea just now.

Is there any other way of doing this, besides putting bigger wheels and tyres on it?

Thanks,

 

[njpumphrey]

My 5sp manual w123 230TE does 80mph at 3000rpm. Are you sure your 280TE is changing into top gear? I didn't particularly like the gear ratios on my 240TD auto - never used first, into third at 20mph, and then into top at 25mph! Perhaps it might be easier to change the gearbox for a 5sp maunal, but I like the thought of Bigfoot wheels on a w123 TE! :lol:

 

[DVF]

Hi,

I checked with the Haynes manual to see what rpm it should be doing. Worked it out from the gear and diff ratios and the tyre size. Got a result of 3050rpm at 60mph, almost exactly what it does do.

A 123 on mega tyres? I saw one of them in a picture once. It was a 123 body mounted on a Range Rover chassis, raised suspension etc. It actually looked quite good!

 

[DVF]

Sorry, it's been a while since I visited here. Too busy at work these days.

Does anyone know the diff ratio of the deisel 123 series cars?

The way my car's running is correct as I said in the previous post, but since I do a lot of motorway miles I would like to change the diff ratio to something a bit more relaxed. Any info appreciated.

Thanks.

 

[Benz240D]

If your trying to put a 280 rear end on a 240D let alone a 300D/TD I would advise aginst it. The enigine on a 240 put out so mush torque it reguires a transmission from a 450/500 series Mercedes. You might find out otherwise and it does work????

 

[joeywarren]

300TD is 2.88 ratio diff and the petrol 280 is 3.6-ish. Longer legs on diesel and the transmission is the same, and is OVER-engineered! Do not fret about that! Do the swap and let us know!

 

[kaapstad]

Hi Dave,

Did you ever swap out that diff on your diesel auto? I have the same issue and am wondering what to do...