Will the steering box from an 84 300d work in an 84 300sd. Thank you

Probably - I'm not 100% sure. There are some subtle differences such as the size of the lock nut on the main spindle. Some W126 boxes have more valves than the earlier boxes. Take a look in the FSM chapter 46-010 for a list of the differences.

I can say that many people have reported here that using the higher pressure steering pumps from a W126 in a W123 doesn't cause problems.

If you are unlucky you might find the steering in a W126 to be a bit heavy at low speeds.

Check the length of the Pitman arms to be sure but I think you'll be OK there too.

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

It will work.

__________________

I LOVE CATS....AND FRIES

1981 300sd
1983 300sd
1985 300d
1983 300cd
1991 350sdl

I have been searching threads if the W123 steering box will work in a W126. seems it will but have to swap the pitman arm.

this is from post# 23 & 27 of this thread.
w123 Steering dead spot, still - after much work

04-20-2005, 10:05 PM
nachi11744
Registered User
Join Date: Jul 2002
Location: Raleigh, NC currently residing in KL, Malaysia
Posts: 460


Quote:
I have a 1981 300SD w126 with overly sloppy steering (its excessive by spec.)
I have a TIGHT steering box out of a 1979 240D (w123)

These look like they MIGHT be interchangeable but possibly not exactly the same. Innards the same? Any ideas?

Part numbers on fastlane are different but....
Hello,
You will need to swop the drop arm to make it work, it may not be as *light* as the W126 box, but in my book, that is a bonus.
Hope that helps.
BTW, check ALL the other stuff before condemning the steering box, like the idler arm bushes etc.
__________________
Nachi11744

Hello,
From what I have been told by the *German tech* that was here in the 1980s to run the MB techs training school, the cars with the Zero Offset front axle geometry, ie W116,123 and 126, place very high loads on the steering boxes and this causes the *premature* wear, like every 100,000miles, you need a new box, but the older W114,115 and 107 front axle DOES NOT do this, so it may be just possible to find a box from a low mileage W107 that is in good shape.
Yes, by *light* I mean the assist will be or at least should be less on a W123 that will have the bigger reaction pistons(smaller reaction pistons=more assist).
Hope that is of some help and does not cause too many sleepless nights agonizing over MB steering boxes
__________________
Nachi11744

Charlie

__________________
there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

Good one Charlie I was a bit concerned about the Pitman arm.

If you need to remove one the chances are that you will have to heat up the shaft and use a puller to get it off. I tried with a Butane paint stripper type burner - it wasn't hot enough. I ended up paying someone to do it for me (Oh the shame)...

I wasn't too fussed about the seals in my steering box as I was rebuilding it anyway, so I didn't make a fuss about someone burning the heck out of the output shaft and the Pitman arm. However, if you want to keep the good one "good" I suggest getting one of those plumbing heat sink mats and covering the end of the steering box before applying heat. At least that will stop any flames going directly onto the output shaft seal (although the heat will travel into the steering box a bit).

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!