Just as the title asks, can a 560SEL driveshaft work in the place of a 300SDL driveshaft? Both are W126 chassis Benz.

While searching for a replacement shaft I came across several ads implying that the two driveshafts are interchangeable. I thought I'd ask the experts here on the forum. Thanks!

os:

Three considerations:

1) The length of the rear section > the same.

2) The length of the front section > different, due to engine length difference.

3) Flex disc bolt circle diameter > different, the diesels use a smaller disc.

Soooo...won't work? That's what I'm understanding. Thanks!

The 300SDL driveshaft is unique to the 300SDL. If you're going through all the trouble, shell out for a good rebuilt/balanced one and do the job once with new flex discs

__________________
Current stable:
1995 E320 149K (Nancy)
1983 500SL 120K (SLoL)

Black Sheep:
1985 524TD 167K (TotalDumpster™)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

I agree, but as I search for them I am finding many of them are advertised as compatible with the 420SEL and 560SEL. I have a good driveshaft for a 560SEL available to me for nearly nothing and just wanted to make sure I wasn't barking up the wrong tree. If the flex disc diameters are different then I'm assuming the mounting pattern just won't come together for a working scenario. I also hate to shell out $350+ because...I'm a tightwad. 😂

560 has a 4 bolt pattern I think...

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

For it's flex disks? Never seen anything but a 6-bolt on this era's MB cars. Different bolt circle diameters but always 6-bolt.

I have searched Pelican and other parts vendors for flex discs for an '87 SDL and for a '91 560 SEL and I keep finding the same part number for both cars. I was thinking it was just negligence on a vendor's part, but three different vendors show that the flex discs for the SDL and SEL in the w126 ('81-'91) use the same disc. What am I missing here? If the flex discs are the same then wouldn't the bolt circle diameters be compatible? 🤔

Yes

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

After checking the FSM on this matter, I stand corrected to this extent:
The flex discs for the W126.125 (300SDL) MY 1986-87 are the larger ones with a bolt circle diameter of 110mm. Hence, the rear section of a 420/560SEL driveline would interchange with the one in the 300SDL.

I very much appreciate your input.