Here's an oddball question: can I convert a '93 940 with regular shocks to Nivomats? All the threads on this topic are the opposite: Nivos to regs. But I'm tired of the rough ride these solid axles provide and I've tried all kinds of shock and spring combinations to smooth the ride out but I don't think it'll ever ride as smooth as Nivomats. So, 4 questions I guess: 1) Will the softer Nivo springs be a direct fit(top and bottom)? and 2) If I take out the little cross bar mounting bracket in the bottom of the shock will it bolt directly to the trailing arm, like a regular shock? 3)Also, what about clearance for the top of the shock which looks much wider than a regular shock. Now I know that IRS systems have a totally different layout which may have more room for the Nivomat setup but '91 940 SE Wagons had solid axles and Nivomats. And, finally, the obvious one 4) On cars designed for Nivomats the shock sits inside the spring. Will it work outside the spring as in a regular setup? If I could find one I'd be able to answer my own questions, but I can't. Any ideas? Thanks

 

960 wagons pre-facelift had nivomats on live axle too

and, I am pretty sure the 760/940se/960 live axle cars, the shocks are NOT in the springs.

 

Thanks Pierce. I'm pretty sure you're right. So the easiest way is to find one of those early 960 wagons and pull the springs and shocks. I did notice that Rockauto does offer Nivomats with the lower crossbar bracket(for irs) and without(for live axles). So, unless the trailing arms we're altered it should be a direct fit. As far as the springs, I haven't seen them offered anywhere so I'll have to find some used ones. And if the shocks are a direct fit I would think the springs are too. I did notice something that surprised me the other day at the local pick n pull. They brought in a '91 940 SE sedan and I measured the thickness of the front springs. They we're 13.3 mm. Never seen that before and I've measured a lot of 940 and 740 springs over the last 2 years. Every other one I've measured has been 13.6 mm. It may not seem like a lot but my spring calculator formula equates that to a 10 to 15 lb lower spring rate, which would match up nicely with the softer ride of the rear Nivomats. I remember you saying that one the best rides you've had was your 780. I could understand the rear being smooth but not the front. Now I know why.

 

not directly applicable, but the Mercedes E class of the same generation (mid 80s to mid 90s) as the 7/9s, in their parts catalog, there's this large complex table, each version of the car has a base 'score', then each major option has points you add to this base score and come up with a number, like 86, you then match this with a table, and choose the correct front and rear springs and spring pads... So, Merc was custom tuning the suspension for each car. It shows, drive a late 80s/early 90s 300E if you ever get a chance, and you'll go WOW. Even on a really rough road, the chassis is rock solid and the ride is smooth and controlled. The Merc 300TE wagons have active hydro-pneumatic rear suspension which is true load leveling.

 

Actually, I've been thinking of buying a Merc from that era, mainly for the ride and better gas mileage. I just wish they looked as good as the 940's. If I do find one it'll have to be '98 or newer. I don't want to risk wiring harness problems.

 

I dunno, I think the 124 series (that includes the 300E, 300TE, 300CE, 400E, and 94-95 E320, E420) look just fine.








(my wife's 1994 E320 wagon, and my 1993 300CE Cabriolet)

 

the wiring harness problems are specific to 1993-1995 model 124's (as well as other models), and virtually every one that was a daily driver and dealer maintained when it was new got a new main engine harness and throttle actuator harness years and years ago, these can quickly be checked via date codes on the label (you want harnesses and ETAs that are 1998+)

the next model E series, the W210, 1996+ are notorious for rust and cracking plastics.

 

They look nice. I guess I like a little less rounded look. And with the right wheels I think it's a great looking car.

Seems strange that a later model Mercedes would have rust problems when the earlier ones did not?

Btw, speaking of harsh rides, I picked up a complete IPD suspension(HD Bilsteins, TME springs, 25 mm bars & poly bushings) and will be posting in classified for about half of what they cost new.

 

those both have the stock wheels on them, 195/65r15. All US 93-95 models used those exact wheels unless they were sold with AMG upgrades.

 

Why do you think the later models we're prone to rust? Doesn't seem like Mercedes to be going backwards technology wise.

Also, I heard the transmissions in these we're weak. Seem to go before the engine does. Have you heard about that?

 

the model 124 series (and 126 S class) were the last models built to an engineering-driven standard, after that competition from Lexus forced them to build to a price point. also, the later cars have a lot more 'gadgetry' in them. the 124's are relatively simple by coimparision.

 

I guess that's what they mean by last of the "hand built" Mercedes'.

BTW, I did a little research and it's not so much the trannys that fail but o rings harden with time and allow oil to seep into the control unit and that causes a lot of "irregular" shifting. Nothing a little maintenance wouldn't prevent.

 

if you're talking about the premature reverse failure on the 4 speed automatics most US model W124's came with, the issue is apparently a weak spring in one of the internal pump/valve assemblies.. the good transmission rebuilders upgrade this, so the replacement transmissions should last like twice as long.

 

There's quite a few mid 90's models for sale in the Bay Area and some have reverse problems and some have problems in all gears(supposedly due to oil leaks into the control unit shorting out the circuit board). As far as the reverse problem being internal, that could cost more than the car's worth? That scares me. What about that inline 6, any weak points you know of?

I've considered buying a Mercedes before but I gave up cuz there's soooo many different model numbers. How can you tell the difference?

 

there's no circuit board on the 4-speed on w124's, its a purely hydromechanical automatic. there's a throttle pressure cable, and there's a vacuum driven 'shift retard' thing on some. later E series (W210, W220) have a 5 speed electronically controlled transmission, or even more gears in later years. I know little about these.

the failure mode of these 4-speeds is first reverse takes longer and longer to engage, then when it gets up around 10 seconds, it stops engaging entirely. optionally, fi you continue to drive it, the tranny grenades inside.

a quality rebuilt transmission for these is about $1800, from SunValley in southern california, or Peter Schmid Transmissions in the SFBA, after core refund. if the original transmission has grenaded beyond repairability, you lose the core charge (its not that much anyways, just a few $100). most benz indie shops will swap one of these for about $1000 labor, +/-.

 

Ok, that explains a lot. I would prefer an old hydraulic transmission over an electronic any day(one of the reasons rwd Volvos last so long). Have you had this problem in any of yours? Or is there an average number of miles when you start to see this?

And I'm going nuts trying to figure out the difference between a c class and an e class?

 

my wifes car made it to 250k miles before reverse let go. my cabriolet is at 245k and its reverse shifting is getting slower.

the buzz on benzworld.com is 150k is typical. they can fail in 100k if they've been lead-footed a lot (along with sloppy things like shifting between reverse and forward while still moving slowly). or they can go 250k if they've been babied. I suspect my cabrio may have already had its tranny 'fixed' (some folks will just replace the failed clutch pack rather than do a full rebuild).

I just figure this into the total cost of ownership... they are definitely higher maintenance carrs than Volvo RWDs, but itsalmost all quite doable, the parts availability is BETTER than Volvo, and the service documentation is pretty good, too, see... Model 124 Maintenance Manual Index M103 is the 2.6/3.0L SOHC CIS-E engine used up to 1992, while M104 is the DOHC 2.8/3.2L HFM-SFI (electronic injected) engine used from 1993+(*). M119 is a 4.2L V8 used only on sedans (400E/E420). OM6xx are diesels, fairly uncommon in model 124 cars.

(*) ok, 1990-1992 300CE coupes used the DOHC M104 as a 3.0L CIS-E version, these are the odd man out.

 

Lots of info. Thanks. The hard part is trying to find a mid '90's, w124 platform with decent mileage, the transmission rebuilt and the wiring harness replaced. I don't know if such a Unicorn exists?

 

Excuse me for hijacking my own thread(again) but Pierce, since I got your attention can u tell me briefly how a Volvo Redblock Turbo controls fuel enrichment when it's under boost? Is it strictly vacuum? (This is for a long term project car I'm contemplating. Basically replace the turbo with a supercharger off a 4 cyl Mercedes)

 

1) complete service records are a very good thing

2) pre-purchase inspection by a reliable independent mercedes mechanic, or even a dealer shop. This will cost $100-200 typically and is worth every penny.

the replacement wiring harnesses have a white cloth "Delphi' tag near the main ECM, this is just aft of the battery, behind a plastic panel, the harness tag is to the car's left side (your right side as you face aft). On the M104 HFM-SFI cars, which are the bulk of the cars with the sketchy wiring, the throttle body tag can be seen looking straight down the gap between the #3 intake runner tube and the central resonance flap thing on the intake manifold, its a green or white sticker (white means ASR, anti-skid control), and if its an updated throttle body, there should be a date code in the format 98M05 (5th month of 1998), in 'dot matrix' on the lower line of the tag, like this one (2005-09)