tx999

I just installed the 2.82 diff from a 94 s420 into my 94 e420. It is the BEST mod I have done to any car. I have spent a ton of money on bmw's in the past. The $350 dollars I spent on the used diff is by far the best. For now its an open diff but I have priced the lsd carrier from the dealer and since I work there I get a good discount. As soon as I save some more $$ its next. Its fun seeing the look on people faces when a 15 year old benz smokes them.
Now I hunt BMW's

AMGDave

TX, do you have a Duc 999? Can't quite tell from the photo. I used to race a GSX-R and currently have an first-gen RSV-R (back when the "R" meant Ohlins & OZ, lol).

Anyway, back on topic... remember if you buy a new LSD carrier for your E420, it won't come with bearings. You'll need to also order the bearings ($$$), and while it's apart you need new O-rings for the bearing carriers, and might as well do new axle flange seals too. As mentioned in my previous post you may need to grind the case to get the LSD carrier to fit, but it is possible. Even if you can pay dealer cost (zero markup), the total cost will be close to $1000 in parts for the LSD carrier, bearings, seals & gaskets, and OE gear lube. Not cheap, but still worth it, especially if your car does not have ASR.

tx999

Yeah, no asr on mine. LOTS of tire smoke, at least from one tire. I am figuring about a grand. I will have more money in the diff and wheels than the car is worth. But worth it to me.
I had a 2005 ducati 999 that I raced in the CMRA until I wadded it up in turn one at Texas World Speedway. 3 months in the hospital and missed 9 months of work. Cant wait to get another.That Aprillia you have is a great bike. If you ever want to sell, that bike is on my list for a replacement.
Thanks for all your help with the diff thing

AMGDave

Oh wow - OUCH!! Very sorry to hear that... 3 months laid up, shoot, you must have wrecked impressively. I raced in the AFM at Sears Point (now Infineon) and Thunderhill on my Circuit-1 prepped 1997 GSX-R750. I still miss that bike. I only biffed it once, in the Carousel (turn 6) at Sears, I was ok but the bike was mangled after spitting 10-15 in the air when it hit the edge of the track. Funny thing was, when the frame was straightened & blueprinted afterwards, the bike handled soooo much better (transitioned much easier). Then I moved to Idaho, and had to sell the bike. No tracks up here except the dragstrip, unfortunately. Funny you mention you're interested in an Aprilia, I have toyed with the idea of selling mine... got 3k on the odo and mostly sits under a sheet in the garage. It's a 2000.5 model, btw. I think I prefer the 4-cyl over the twin after having owned both. I'd like to get an F4 312 but besides the fact I can't afford one, I'd probably lose my license!!



Yep, as long as you've figured $1k, you're right on target. The good news is, if you ever sell the car, you could always remove that diff and sell it for at least $1k, to recoup your investment. If you do buy the new LSD from the dealer, could you post some photos of it? I've never seen one brand-new. I got a used one and rebuilt it, which wasn't really worth it. I spent far too many hours on the rebuild, for the couple hundred bucks it saved. I'm hoping to have it completed within a few weeks (still waiting on those shims, as mentioned in my post from a few days ago) and installed within a couple weeks after that.

AMGDave

My 2.65 LSD project is completed. It's in the car and working fine so far. I used a Yellow Box speedometer converter (www.yellr.com) and was able to get the speedometer accurate within 1mph from 0-100mph (compared to a GPS), and the odometer accurate within 1%. That's good enough for me. I should have the car at the dragstrip in 2 weeks, and hopefully the LSD will have cured my traction issues.

The only drawback is, the ASR (traction control) system doesn't like the LSD during low speed turns, i.e. accelerating through a "square" turn from a stop sign or traffic signal. The ASR engages even though there is no wheelspin. I think this is due to the action of the clutch pack where it "grabs" slightly. Even though you can't feel it from the driver's seat, I suspect the ASR sensors are getting a voltage spike from the clutch pack "clicking" as the spider gears turn, which engages ASR.

Interestingly, if I turn on the snow chain switch (or shut of ASR entirely) the problem disappears. Shame there's no way to engage the "snow chain" program all the time. It would be interesting to see if a Quaife ATB would eliminate this problem... there does appear to be a Quaife available that may fit (it's not shown in their USA catalog), but the cost is approx $1400 - ouch. I think I'll live with the problem unless I can get the Quaife for less somehow. It's also not certain if the Quaife will fit in the 124/129 diff housing... may only work in early 126/107 housings. I'm still checking into that though.

dernt

Dave,

How easy was it to wire in the yellowbox? Did you put it behind the cluster? I took my cluster to an authorized VDO shop for recalibration, but the guy is a goober. He has the speedo dialed in because it adjusts with a trim pot, but he cannot figure out how to get the odometer even close. I think I will tell him to set the speedo back to stock and get a yellowbox. That's gonna be a waste of whatever this knucklehead charges me for the two weeks he's been fiddling with this.

AMGDave

It was a breeze... taps in directly at the connector behind the cluster. And yes, I did install it behind the cluster, it's small enough to tuck in there (see photo below). If you order one, make sure you specify that you need the 2-wire model for inductive speed sensors (this is not shown on their website - you have to email them and/or put this information in the "Order Notes" box).



LOL! Yeah, sounds like that shop doesn't know the electronic units intricately. The place that modified mine was able to adjust the speedometer and odometer separately. The modification on mine was different than most because I changed to a 190mph speedo face, which requires different adjustment for speedo & odo. Yours would be much more straightforward since you're keeping the same 160mph speedo faceplate. Dunno why the guy can't figure it out, apparently he's never done it. I'd ask for it to be set back to stock and there should be no charge since he didn't do anything!

dernt

Dave, was the wiring straight forward? Can you tell me what color wires you spliced and/or tapped?

I thought you had a 500E? Are you also working on a 400E? The 500 comes with 2.65s, right?

AMGDave

It's the square, 4-pole connector at the back of the speedometer, which has 3 different color wires going into it. Black/red is the switched +12v, brown is ground, and white is the signal wire from the tranny sensor that you cut & re-route through the converter box. See the ETM (Group 24) in the FSM, printed page 136/8, PDF page 116 (of 275)... I also attached it below.



I actually have both (see my signature below). The 500E / E500 comes stock with 2.82 gears worldwide. The 400E / E420 has 2.24 gears in the USA & Japan, and 2.65 gears in the rest of the world. I plan to swap gears in the E420 also, I'm undecided at the moment if I want to install 2.65 or 2.82 though.

dernt

Oh, duh!

Thanks for the wiring info. I am going this route.

PhantomLord

Dave/Dernt,
My cars differential is scheduled for a replacement due to drive train issue. Just wanted to re-confirm few things before going for ASD diff instead of normal one.

If there is ASD diff available with same ratio and gears(185mm), is it a direct bolt on for car with open diff? If not what mods?

What happens to Hydraulics connection on diff end?

Thank you

AMGDave

If your car has a 185mm diff with ABS only (no ASR), then yes, you can swap in a 185mm ASD diff. The hydraulic ring cylinders can be removed. You replace them with normal axle flanges and the matching seals. The input flange will need to be swapped if it's not the same, also the rear cover. And finally, if you are buying a used ASD diff, the clutch pack will probably need replacement.

I did this exact swap on my 124.133, it worked great... photos are located here. You will probably need to buy or borrow some of the required tools. It's not a cheap project, but I've been very happy with the results on my ABS car. (I'm not so happy about the ASR car, but that's a different story).

PhantomLord

Thanks for input and pictures Dave, Current one is ABS only Diff. Rear cover part on both are same, I am assuming input flange would also be so.

I am planning to buy a sparingly used diff without replacing clutch pack for now. Can you please list tools and parts that I might needed for replacing hydraulic ring cylinders with normal axle flanges.

AMGDave

It depends on the exact model of each car... but if they are similar engines, then yes, the input flange could be the same. This saves you some work, as long as the pinion seal isn't leaking, just leave it alone.




It will be tough to find a low-miles, "sparingly used" diff. But if you can find one, great. Just remember you'll have to tear EVERYTHING apart later on to refresh the clutch pack. With everything torn apart already during the swap, the labor is almost free, you just need to fork over the ~$300 USD for new clutches.

The assorted tools are shown here, note that the friction moment tool and pinion nut tool are not needed if you're leaving the input flange alone. You will need a set of large snap-ring pliers to R&R the snap rings. If you're just swapping carriers, you most likely won't need to re-shim it, but a dial gauge will confirm that backlash is the same before & after. The parts are all shown in the first link, you'll have to get the part numbers from the EPC for your application though... it's all straightforward, nothing special involved.

taxi driver

Hi, time to update this thread and ad some more fuel ?

Dave has done a very thorough research on how to convert ASD,LSD etc.
thankyou for that work and very good pictures also.

Now I am sitting with a 3.06 ASD eightbolted ringcylinder housing originating
from one '93 E320 t model, does that spell it's a 210mm diffhousing?

As I have seen i'ts possible to convert 185mm ASD diff to a true LSD
by replacing the outputshafts and reset frictiondisc preload and get rid of
the ringcylinders.

It does not seem that easy to do the same operation to the eightbolted
counterpart.?

Now that I am going to use this diff in my W202 wich has 3.07 gearing there's
one option or two, use the ASD unit as it is reset the preload or operate
the ringcylinders in some suitable way preferably by action from the
ESP off switch. Also the halfshafts needs to be shortened to compensate
for the wider ASD diff.

Doing this to a 2.82 ASD would also be nice in my 500E if I do not find any
W126 donor LSD carrier, if it was'nt for that DAMN ASR sensors!!

Btw is the 210mm ASD carrier by chance usable in std 210mm housing??

A lot of questions but someone must have tried or researched some of it. Roger

AMGDave

It depends on the ASD carrier, and which housing you are using. However I was able to use an early ASD carrier in my 1994 E500 diff, as detailed earlier in this thread, with a link to photos. Some grinding is required to get the larger ASD/LSD carrier into the ASR housing, and the LSD interferes with ASR operation at low speeds when turning, but otherwise it works great.

taxi driver

Good, so I assume the 210mm eightbolted ASD flange can be changed to the
non ASD flangeseal and output shafts respectively and setting the friction
discs to funktion as a LSD ? Roger

taxi driver

I have been talking about the 3.06 ASD diff from a E320 that I found at the
salvage yard and was going to use in my C43 ( it's a lot of that in the C36/43
thread also alot in the 500ecstacy forum, now I found out, the 3.06 eight
bolted flange cylinder/sea housing has a part# for the diff unit 126..... ASD or
140.....open diff, the housing has a124..... part#!?

That must also mean this 210mm ring gear ASD carrier can be used in the
210mm ASR housing , maybe some modification needed as you said. Roger

John Bicht

AMGDave, this is a thrilling thread! I have wanted for years to put an LSD in my 400E - which has ASR. Somewhere else I have come across the information necessary to defeat the ASR. Have you tried this to get rid of the slow speed problems you mention with this arrangement in your car? I don't doubt your diligence, nor knowledge, especially after this thread, but I did wonder since we have an excellent, but high mile 400E that we wish to keep.

AMGDave

Hi John, yes I do have the ASR defeat, but only use it at the track... ASR is still an excellent safety feature for street use and I don't normally drive with it shut off. The low-speed problem when turning has lessened considerably now that the LSD clutches have broken in for a few thousand miles. At first the new clutch pack was pretty tight and that made the ASR intereference worse. The problem still pops up at times but it's not as bad. I still just use the snow chain trick when I need to pull out from a side street in a hurry. The LSD has done the intended job though, and made my dragstrip launches far more consistent.



If you want to put LSD in your 400E, you'll need to decide what gears to use. If you want LSD with your stock 2.24 gearing, that could be expensive... the LSD for that is roughly $1500 USD (plus misc parts & installation). The LSD unit for the 2.65 or 2.82 gears is much cheaper (almost half) but of course that would mean additional work, sourcing the spare diff, and correcting the speedo. David Hendy has a couple of 2.82 diffs from a 500E available if you're looking for one. That would be the easiest swap.

John Bicht

Thanks for responding so quickly AMG.

Is the ABS function included in the ASR description? Having had ABS on other cars, and hating the wheel-spin aspect of ASR from the start, I never thought of them as part of the same package. Is that the safety feature of the ASR that you mention?

While I definitely want to change the gearing, I think 2.82 is too much and the 2.65 would be just right. We spend a lot of time on western interstates. I need to re-read the thread to have a firmer understanding of the options as already stated.

AMGDave

The ASR defeat leaves the ABS function intact, no worries there. However with limited slip and no ASR, the rear end can come out quite easily on wet or dirty pavement... while a skilled driver may be able to compensate for the unexpected oversteer, a less experienced driver can end up spinning into a ditch, telephone pole, oncoming traffic, etc. Not good if your spouse or teenagers may occasionally drive the car. ASR will prevent the problem. It's a good safety net.

You can experiment with this by disconnecting one of the front wheel speed sensors temporarily (note that this will disable both ASR and ABS) and going for a test drive. When you re-connect the sensor, you should clear the error code in the computer, but that isn't necessary (the dash lights will go off once the sensor is reconnected). The traction problem will be more severe with lower gearing of course, and/or with stock tires vs wider wheels/tires.



I agree, I think 2.65 would be great. Just pick up an early 129.066 diff with ASR, pop in the LSD unit, and bolt the whole thing in along with a speedo correction box. You may have issues with the axle speed sensor calibration as you have to use the 124 sensors (the 129 sensor wires are too short), but don't worry about that until you have all the parts on the bench - it's basically the last thing to tweak prior to installing the whole thing in the car. That is one big advantage to the 500E diff... no worries about sensor calibration as you would use the same sensors, shims, gearing, etc.

John Bicht

I still do not quite understand. I drove roadracing cars for decades (60's and 70's) with LSD. My English Alfa GTV 2000 had a clutch pack type diff. Nothing ever felt so good driving as a car with limited slip. That is one of the reasons that I am so excited by discovering that I can put one in this great car. I never felt that an LSD car was dangerous. In fact I feel it adds a degree of control that an ASR car can't get close to.

Porsche 911's and such have limited slips and much higher power to weight ratio.

And please take no offense. None is intended, simply trying to get a better understanding.

By the way a stock 400E does not appeal, but our suspension kitted (lower stiffer) 205/55-16 wheels and tires, the wheels modified and both them and the grille powder coated to match the smoke silver car, does work quite well.


How did a 500E use a 2.82 gear and and have a good top speed. A different transmission ratio? The 400E gives a top speed of 147 (I think, although I only usually go to 120) which proportionately a 2.82 gear would lower to 116? What am i missing?

Regarding the sensor wire problem, why not extend the 129 wires?

I am not certain where I can get the LSD unit at wholesale, any body on the forum?

Where did you source the details of diff setup, clearances, torques, etc. Do MB not recommend new bolts for the ring gear each time?

AMGDave

You are speaking about a skilled driver - and sure, most skilled drivers prefer not having electronic nannies like ASR spoiling their fun. Remember, I was talking about unskilled drivers with 300hp on tap in a rear-wheel drive car... for those folks, ASR helps keep the sheetmetal unwrinkled. But I never meant that LSD was dangerous. Interestingly, ASR can translate into quicker lap times, despite the vast majority of people claiming the opposite. Click here and read both pages of the article. Just because the car *feels* faster with ASR disabled doesn't always translate into quicker laptimes via stopwatch!



Nope, same transmission ratios. The 500E is governed to 155mph in stock form, but if you bypass the governor it will be redline (gearing) limited at approx 162mph (at 6350rpm). The 500E has slightly larger tires as well but that only tweaks things a few percent.



The early 400E was power limited at 147mph due to the tall gears and smaller engine. The late 400E/E420 was governed to 130mph to allow H-rated tires. The 400E with 2.82 gears and stock tires would likely hit 155mph if the governor was bypassed, pushed to the 6350rpm redline. Although 2.65 gears would theoretically push the top speed past 160, I'm not sure if the 4.2L motor has the power to shove it through the air.



That is a definite possibility, as long as there isn't shielding issues or electrical interference. (??)



It's an OE dealer part, lowest price will be via Parts.com, with the "Freight-Quote" shipping option it should be $771 plus shipping (maybe $20-$30 or so). Standard shipping is 15%, which at $115 is obviously silly. This is for the 2.65/2.82 LSD, btw. You'll need new bearings as well, and new seals would be a good idea.



Factory service manual. And yep, MB recommends new bolts for the ring gear, although I think I re-used mine.

John Bicht

Great information. I finally went out and checked the revs/mph and might be quite happy with a 2.82.

How do I reach Dave Hendy to get a price for one of his diffs?

The only manuals I could find were the pretty crappy CD ROM stuff - which I wouldn't imagine would have this information. Where do I get this wonderful thing (service manual) that I thought wasn't available?

Parts.com had not way to search on a part number so I was quite stuck trying to get to the right part and shipping. I even emailed them, apparently so far to no avail. Ideas?