Wheel size 1985 300D vs. 1985 300SD - PeachParts Mercedes-Benz Forum

rtykw2 · #1 08-03-2004, 09:24 AM

My '85 300SD needs new tires. My uncle just gave me a wrecked '85 300D with new tires on it. I did some seraching on the forum, but was not able to come up with an answer. I want to know if I can just swap the wheels from the D to the SD, or are they not the same width of rim?

Thanks.

MTUpower · #2 08-03-2004, 09:32 AM

Many W126's (SD)came with the "bundt cake" rims - 14x6.5 with a offset of 30. These rims were also very common on the W123 (D). Some W126's had 15 inch rims, so the best way to see is to put one from the D on the front of the SD and check it.
William

sixto · #3 08-03-2004, 06:45 PM

Compare the stampings on the backs of the wheels. The numbers to look for will be of the form 6Jx14H2 ET 25 or something like that. The 85 300D and SD both came with 14" wheels but who knows what's on there now. 6 or 6.5 (6,5) in width shouldn't matter as long as you use a matched set.

Sixto
95 S420
87 300SDL

thebenzbar · #4 07-14-2005, 01:54 PM

The wheels from that 300D (w123) will fit on your 300SD (w126) - whether they are either 6"x14" or 6.5"x14". And both chassis have nearly completely interchangeable wheels due to the close similarity of offsets....

ayalar007 · #5 07-14-2005, 02:32 PM

What is 'offset???' I'm really ignorant when it comes to that!

thebenzbar · #6 07-14-2005, 09:50 PM

Quote:

Originally Posted by ayalar007

What is 'offset???' I'm really ignorant when it comes to that!

The offset of a wheel is the distance from its hub mounting surface to the centerline of the wheel. Check various online sources such as tirerack.com or google other wheel sites...plenty of info out there for "wheels 101"...

diametricalbenz · #7 08-31-2006, 03:36 AM

Are the 6.5" tires unique to the 6.5" wheels or can they be used on 6" bundts?

Samuel M. Ross · #8 09-01-2006, 02:51 PM

a 300D and two 300SD(s) and not had a problems. These are all 14-in and so I would think that so long as you are changing 14-in for 14-in and you don't mix the offset of the wheels that are mounted on the ground, you should be OK... with one possible thing I don't think was mentioned. Did you say what size the good tires are that you want to use? I ask because many W123 chassis models will have smaller 195x70x14 size [not sure of these #s] where as the 300SD(s) have a slightly larger tire... 205x75x14 tires. Again, I'm entire sure of the #s because I'm on the road now away from these cars.

I would not put the smaller tires on the larger, heavier 300SD W126 car.
Sam

#9 09-01-2006, 03:07 PM

I've used 185/75-14, 195/70-14, and 205/70-14 on W123s. I agree, you should not use smaller than stock tires on the W126.

sixto · #10 09-01-2006, 03:19 PM

Quote:

Originally Posted by Samuel M. Ross

where as the 300SD(s) have a slightly larger tire... 205x75x14 tires.

I would not put the smaller tires on the larger, heavier 300SD W126 car.

Per the owner's manuals of an 81 and 83 SD, they take 195/70-14 tires. The V8 W126s of the same years take 205/70-14 tires.

You should be as concerned about the load rating. A load rating of 86 might not be safe for a W126. You might need something in the 90s. The W140 takes something like a 97. I don't know where these specs are provided if provided at all. Luke in the Tire forum will know.

Sixto
93 300SD