Limited slip diff doubts...
 

Hello guys!!

I know the LSD swap from a W126 to a W123 has been widely discussed here, but I still have a doubt that no one has mentioned AFAIK.

Here's the deal: I want to install a LSD I got from a 380 SEL into my W123 300D. However, I would like to keep the gear ratio I have in my 300D. Is it possible to use my crown and pinion with the LSD satellite box? Please excuse me if I'm not using the proper terms... :o

Thanks!!

are you sure the 380 SEL had a LSD? if you have the part number from th unit or the donor car vin i can verify for you

I didn't think the 380's had limited slip, I know the later 420's did not.


How the heck do you install a W126 diff in a W123? Are they that similer? Do you have to weld up some sort of bracket?

yea, my thoughts also

it might if a euro.

tom w

hey guys, some extra info. It's an euro 380 sel, which I'm sure has the limited slip diff because I drove the car just before it was parted. I'm not sure about the year, but it's somewhere near 1983.

About swapping the diff from a w126 into a w123, its possible it the donor is an early w126. They even have the same housing number. However, the my 300D has a 1:3.46 ratio, while the w126 diff I have has a 1:2.47 ratio LSD. As you can see, the W126 diff is way faster.

I really don't want to loose the actual ratio, as my 300D performs really good as it is. I just want to have the advantages of a LSD as well.

Any idea if I can use the satellite box from the w126 with the crown and pinion from the w123?

BTW, some might say I can use the advantage of a faster gearing ratio to save on fuel, but I already have a 5-speed swap planned, so no need for the faster ratio. ;)

for sure! not to mention a 2:47 would melt your clutch in short order!
John

there should be an id tag on the unit that indicates if it is a lsd, thould be attached to the rear diff cover bolt.

If you find you can't change the ratio, I'd be happy to take the 2.47 off your hands. I'm already running a 2.88, and I'd go lower if I could. :D

I really would like to know if the crown and pinion swap is possible, before doing all the job of taking my diff out...

count the teeth on your pinion you have out. if it's the same, you should have no problem getting the gears swapped.
I don't know if the pinions are the same on the LSD versus straight dif.
John

oky doky, I'll take a look as soon as I get a chance. Maybe on sunday...

BTW, just wondering, does anyone know which series of the 617 Turbo engine was the best performing one?

None stock.

afik they are all the same.

but if there is any difference,...

i suspect the early 116s might have a bit more poop.

tom w