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I don't know what the break point is for this... probably has to do with blue top solenoids in the valve body... but I have a RaceIQ TCU and the paddles work in every mode EXACTLY as they did stock... but quicker shifts.
Mine is an '06 but IDK whether '04 had the blue top solenoids.
Let's see what what the RT TCU does for Joe.
I actually have a spare of some TCU, just not sure which at this point, RaceIQ or MKUltra. Both will be surplus soon as I think I'm going back to full stock everywhere.
maw
Maw, if one of them is the one I sent you when I went back to stock, it's an MK Ultra with Agility Mode. Here's a Transmission Tale. I'd been experiencing rough shifts since the day I got the car. First thought it had something to do with the MK Ultra TCU but when I installed the stock TCU provided by the PO who'd installed the MK Ultra, there was no change. That TCU had experienced wicking but had been cleaned and when tested during a pan-off transmission service wouldn't show a VIN or accept SCN adaptations. Figured it was shot and installed a stock TCU from MK Ultra that had been coded to the VIN. The shifts improved slightly but were still pretty rough and at that point I figured my issue was valve body / solenoid related as the PO had replaced the conductor plate just prior to selling the car. Priced out a MB remanufactured valve body with a full set of solenoids (including blue tops) today and came up with about 1,800 bucks. At that point I figured what-the-hell, and God Forbid grabbed a can of Seafoam Transmission Tune. Siphoned approximately a liter of hot fluid and found that brought the level down to just below the bottom "hot" line on the dipstick. Added the 16 oz. can of Seafoam, ran the car through the gears a few times in the garage, checked level again and Lo and Behold, it was exactly in the middle of the two "hot" lines. Pulled out of the garage and couldn't believe the immediate improvement. Shudder gone. Shift lag gone. Smooth and quick. All-in -all a pretty impressive transformation. Took a 50-mile spin just to enjoy what I'd been missing. So, was it the Seafoam or had the tranny been overfilled not once, but twice? I don't know but I'll run it with the Seafoam for 100 miles or so and do a fluid change with FUCHS 4134. And check the level very carefully.
Last edited by CICBarkeep; Mar 3, 2025 at 09:32 PM.
Well MAW, you were spot on. Ebay TCU came and in the same condition as my factory TCU. Covered in oil on the inside and with the same round capacitor broken off and rolling around on the inside.
I Pulled it apart and gave it the same treatment, cleaned it really well with contact cleaner and re-soldered the capacitor. Nothing. Only now it is actually showing me what gear I am in (P R N D-S), however it is stuck in S mode and still locked in 2nd gear. I can not select manual or comfort mode and the paddles do not work.
I even attempted to pull the TCU out of my CLK55 and swap it, but it wouldn't even turn over with that TCU, so no dice there.
I found a guy on FB selling a TCU and i asked him to open it up and inspect. Same thing, covered in oil and he was shocked.
So, what to do now. I have to find one that i know for a fact is clean. Autohub on eBay is the company i bought the last TCU from, and they are offering a refund. They have other on their eBay store listed as an R230 SL55 TCU which only had 40K miles on it, however its $290. I may have to bite the bullet, not sure where else to go.
I have a friend of mine who is an electrical engineer and works with auto manufacture modules all day long. He said he'll come over and run some tests on everything and see if we can narrow it down to anything further, however he seemed quite certain the issue lies with the TCU.
What most of these tuners were doing, as of a couple of years ago, was buying old factory modules, reflashing them then selling them. That's why I still have my original TCU. So I'd say get it now while you can before the supply dries up.
I wish I had gone that way with my ECU, but I suppose flashing that back to stock won't be problematic. Then I'll just pop in my original TCU and have a nice day.
For this car, "I hate it when I'm right" is what comes to mind. I owned it for 10 years before I tuned it because "best left bone stock" was my instinct. I went against that instinct, because experience is better than theory. But now that I've had the experience, the car really is best left bone stock.
This is the exact route I'l be going. I was under the assumption you needed to send in a core that was certified to be working properly. I did not know they supplied the TCU.
'06 MB S55 AMG; '04 Audi Allroad 4.2; '05 BMW M3 Conv.; '92 MB 500E
Originally Posted by PHILLYCLSJOE
This is the exact route I'l be going. I was under the assumption you needed to send in a core that was certified to be working properly. I did not know they supplied the TCU.
Joe,
MK Electronics has stock TCU's that can be coded to your VIN for $130.00. While I didn't open mine up to check the inside, it arrived bone dry and has remained that way. Helped the shifts to some degree, but what really made a difference was siphoning enough tranny fluid to bring it to the proper level. Not real happy with my Indy. Overfilled my ABC fluid too.
'06 MB S55 AMG; '04 Audi Allroad 4.2; '05 BMW M3 Conv.; '92 MB 500E
Originally Posted by CICBarkeep
Joe,
MK Electronics has stock TCU's that can be coded to your VIN for $130.00. While I didn't open mine up to check the inside, it arrived bone dry and has remained that way. Helped the shifts to some degree...
Not real happy with my Indy. Overfilled my ABC fluid too.
What are you doing for the ABC fluid, siphoning off the top from the reservoir while cold? I'm gonna check my fluids before I take it out today.
What are you doing for the ABC fluid, siphoning off the top from the reservoir while cold? I'm gonna check my fluids before I take it out today.
maw
I misspoke, they underfilled the ABC and overfilled the transmission. But yes, if the reservoir is overfilled even a turkey baster would work. Caught the ABC early on and keep a close eye on it. Basically, every fuel fill and it hasn't been an issue since I added fluid. (Carry a can of Pentosin in the trunk JIC) Can't say why I waited so long to check the tranny fluid. It's definitely shifting better since I got the level right but it's a matter of time before the valve body/solenoid swap will have to be done. Simple job if you have access to a lift, but like Joe said earlier a real PITA if you don't. And I don't.
'06 MB S55 AMG; '04 Audi Allroad 4.2; '05 BMW M3 Conv.; '92 MB 500E
Originally Posted by CICBarkeep
I misspoke, they underfilled the ABC and overfilled the transmission. But yes, if the reservoir is overfilled even a turkey baster would work. Caught the ABC early on and keep a close eye on it. Basically, every fuel fill and it hasn't been an issue since I added fluid. (Carry a can of Pentosin in the trunk JIC) Can't say why I waited so long to check the tranny fluid. It's definitely shifting better since I got the level right but it's a matter of time before the valve body/solenoid swap will have to be done. Simple job if you have access to a lift, but like Joe said earlier a real PITA if you don't. And I don't.
Yeah, I keep Pentosin in the garage for water burnoff over time, etc. After the fluid / filter / accumulator services the level will change while driving the car. So that's all fine. Not sure I'd keep it in the trunk because it smells so bad and if it spills.
Did you ever get the Seafoam out of the transmission with a flush? If not, I'd do that. A noted Mercedes transmission builder cautioned me that it's not what goes into the Mercedes transmissions that hurts them but what doesn't come out. Mercedes seals don't always like the additives over time. So from that advice, I would not leave Seafoam in there for any length of time. In fact, I just resorted to fluid changes more often and no additives.
maw
EDIT ... just checked and adjusted mine, from needing a new tandem pump over the winter (16 years ownership and 160k miles, no biggie). The level was "close" but needed a couple ounces in the reservoir when dead cold (sitting in the garage for months).
Funny thing that... for the last few years she would sag "a little" after sitting weeks like that, and I refused to believe it was a valve block. Well, now that the tandem pump is new, no sagging this winter. I guess the same leak that was letting out fluid was letting out pressure. Makes too much sense.
Yeah, I keep Pentosin in the garage for water burnoff over time, etc. After the fluid / filter / accumulator services the level will change while driving the car. So that's all fine. Not sure I'd keep it in the trunk because it smells so bad and if it spills.
Did you ever get the Seafoam out of the transmission with a flush? If not, I'd do that. A noted Mercedes transmission builder cautioned me that it's not what goes into the Mercedes transmissions that hurts them but what doesn't come out. Mercedes seals don't always like the additives over time. So from that advice, I would not leave Seafoam in there for any length of time. In fact, I just resorted to fluid changes more often and no additives.
maw
EDIT ... just checked and adjusted mine, from needing a new tandem pump over the winter (16 years ownership and 160k miles, no biggie). The level was "close" but needed a couple ounces in the reservoir when dead cold (sitting in the garage for months).
Funny thing that... for the last few years she would sag "a little" after sitting weeks like that, and I refused to believe it was a valve block. Well, now that the tandem pump is new, no sagging this winter. I guess the same leak that was letting out fluid was letting out pressure. Makes too much sense.
We're on the same wavelength and I'm waiting for the FUCHS 4134 ATF to arrive as I type this. Flush will be done when it does. Hopefully no later than tomorrow!
We're on the same wavelength and I'm waiting for the FUCHS 4134 ATF to arrive as I type this. Flush will be done when it does. Hopefully no later than tomorrow!
Flush should be easy enough if your just pulling the drain plug and refilling (and should be adequate as well) However, do yourself a favor and buy a good, quality T-(whatever bit) fits the trans drain plug. As Mercedes states the ole "Lifetime Fluid" i don't think my drain plug has ever been opened. Upon trying to open it, i snapped off a cheap T-Bit end inside the drain plug. Considering i was dropping the pan regardless for the conductor plate, i just let it drain from the seal. What a mess and a nightmare lol. Once i got the pan on the bench i was lucky enough to be able to get the broken T-Bit out of the drain plug.
Also, What are you using to measure fill level? I was curious about this when refilling. I used the entire Jug that was sent with the kit from FCP euro which i believe is a gallon, but i'll have to look, and a cheap dip stick off of eBay. Not the most accurate but it gave me an idea of how much fluid was in the bottom of the pan. Stick it in, pull it out, looks about right but who the hell knows.
I ordered the MK-Ultra TCU so we'll see what happens, and i'll be sure to keep you all posted. Thanks for all of the feedback
Last edited by PHILLYCLSJOE; Mar 7, 2025 at 02:07 PM.
Flush should be easy enough if your just pulling the drain plug and refilling (and should be adequate as well) However, do yourself a favor and buy a good, quality T-(whatever bit) fits the trans drain plug. As Mercedes states the ole "Lifetime Fluid" i don't think my drain plug has ever been opened. Upon trying to open it, i snapped off a cheap T-Bit end inside the drain plug. Considering i was dropping the pan regardless for the conductor plate, i just let it drain from the seal. What a mess and a nightmare lol. Once i got the pan on the bench i was lucky enough to be able to get the broken T-Bit out of the drain plug.
Also, What are you using to measure fill level? I was curious about this when refilling. I used the entire Jug that was sent with the kit from FCP euro which i believe is a gallon, but i'll have to look, and a cheap dip stick off of eBay. Not the most accurate but it gave me an idea of how much fluid was in the bottom of the pan. Stick it in, pull it out, looks about right but who the hell knows.
I ordered the MK-Ultra TCU so we'll see what happens, and i'll be sure to keep you all posted. Thanks for all of the feedback
Joe, thanks for the heads up on the bit, but my guess is the plug's been out at least twice before I got the car and once when I had the pan-off service done at my now somewhat suspect MB only independent. I bought a dipstick thru FCP Euro quite a while back and have been using that to measure. After siphoning a liter of fluid and adding 16 oz of Seafoam the level comes to exactly the middle of the two "hot" marks, and I gotta' believe that's where we want to be. Picked up a $2.69 drip pan with liter markings at WalMart yesterday and I'll use that to get an idea how much to replace and use the dipstick from there. Good luck with the TCU, sure hope that solves your problem. Sounds like a real PITA.
Looking good MAW! I'm sure it was an enjoyable ride today. looking forward to enjoying the fruits of my labor here soon.
While waiting for the TCU to come in I was able to tackle another large maintenance item today, Motor mounts.
Everything on this car is Easy and Hard. Took me every bit of 8 hours. The old mounts were not torqued down as the top bolts came out with barely any force. The small 16MM wrench you can get off of the Jungle site was certainly a big help, however i would strongly recommend a short 16mm ratcheting wrench, due to only being able to turn the driver side top bolt barely a quarter turn each time. Swinging over to the passenger side top bolt was a real pleasure even tho that wasn't very easy either, but you can get almost a full rotation. ABC pump and lines are in the way on the driver side. Also a borescope is a HUGE help.
Drop the entire Steering rack bracket for this one, and push it back towards the rear of the car as much as possible. It's tight, but you can swing both mounts in. Also, jack the engine up high. I had a board that was too long, only allowing me to jack the engine up flush with the front crossmember. Scrapped it for a short piece and got much more clearance for the mounts. Old mounts were collapsed and I've noticed the engine sitting up a little higher now. Dip stick is not hitting my split cooling tank any longer which is nice.
Next up is to rebuild both valve blocks and figure out what i'm doing regarding the headlights. I won't be able/willing to drive the car at night with the driver side beam flickering on and off.
Really Looking forward to a warm spring day here soon when i can spend a full Saturday/Sunday on a proper detail. The entire underbody and engine compartment is so filthy from that oil line that burst, it needs a deep clean.
Last edited by PHILLYCLSJOE; Mar 8, 2025 at 06:27 PM.
I don't know, you would think these cars/Transmissions should be able to handle that kind of abuse, no? Unless it was already on its way out and that did it.
I would like to believe burnouts and donuts shouldn't really be an issue, especially with the amount of power they supposedly can hold before cracking them open.
MK-Ultra TCU came in today and I was able to install it. Everything seems back to normal and it's running and driving great once again.
I went through the Adaptation process then took it for a good 20-30 mile drive up the highway to stretch its legs and get some fresh V-Power Shell Fuel.
Shifts feel much faster then before. Got into it a little bit but nothing crazy, as i think the TCU is still in its learning phase.
One major benefit I've noticed which was outlined in the Overview of the tune was the faster downshifts related to throttle response. Light input in the Go pedal and she's dropping a gear much sooner then before, which i like. I believe i was driving in the A "Agility" mode.
All other selections seem to operate as they should. I'll have to mess around with Full Manual mode which holds the gear once i drive it a little more.
Overall very happy with the Tune, Thanks for the recommendation!
She's filthy, but Damn it sure feels good to be back in the driver seat enjoying this car once again. I'm still getting vibration in the wheel and the overall feel of the car that i'm going to have to narrow down. Could be tires, could be the driveshaft rubber donuts, could be the carrier bearing, not sure just yet. However the motor mounts made a big difference.
Lastly, It still doesn't feel like its running 100%. I think i might have a Vac leak coming from somewhere as theres just a slight hesitation both at idle and quarter throttle. It's not bad but certainly noticeable.
'06 MB S55 AMG; '04 Audi Allroad 4.2; '05 BMW M3 Conv.; '92 MB 500E
Good stuff Joe.
One thing you might notice but not recognize is now you can make double downshifts (4 to 2) with two clicks on the steering wheel. Stock would impose a delay which most TCU tunes do not. I enjoy that.
Also, do the pedal hold reset while in ACC mode (key turned, dash lit up, engine not running), to help the TCU marry up with the ECU. That'll get you your 100%.
If you had a vacuum leak you'd have a CEL. If you're running boost, run 1 step colder plugs to get your 100%. On a tune these things will absolutely lean out at high RPM (less than 100% power).
I pretty much only drive in full M mode, since I've owned the car, so I can't comment on what these TCU tunes do when not in M mode.
1 step colder plugs were installed, along with wires and coil packs which are all new. I'll have to take some time and narrow it down.
I did notice the 4-2 and 3-1 down-shifts, which automatically happen when i click the stick down 1 time. It will drop it in the lowest, best gear possible without having to hit it twice.
This was their "SLR Black Series" map which i believe they just released. It's been improved in a few different areas apparently.
First impressions are very good however. I think once it learns and matches the TCU it will be a real pleasure to drive. I'll likely be driving this down to Florida again come late April, and i'm sure that will do it some good.
Last edited by PHILLYCLSJOE; Mar 17, 2025 at 08:55 PM.
Joe, your post just saved me a ton of money! I needed a new valve body and was right on the verge of spending well over $800.00 to get a remanufactured unit thru MB Parts. I'd checked to see if these guys had them in the past, but they were always out of stock. Anyway, your post prompted me to check again and lo and behold, they had a rebuilt AMG 240-0106 valve body that comes complete with new Sonnax overlap sleeves, Blue Tops, Shift Solenoids, the TCC and Conductor Plate for 500 bucks after the $100.00 core refund. Yeah, it's 'rebuilt' instead of 'remanufactured', but considering what all is included and the fact it's been sonic cleaned, and vacuum tested I'm feeling pretty darn good about ordering it. Gotta' love the forums! And MK Ultra!
Beautiful! Glad it worked out, and so far I'm incredibly impressed/pleased with their TCU Tune after driving the car a bit more. My absolute favorite aspect of the tune is the quicker downshifts related to throttle response. It really changes the whole dynamic of the car and makes it feel much less sluggish to get its *** up and moving. Not to mention the feel of a slightly more modern transmission.
Will you be tackling the job yourself or having it sent to a shop? As i said not a terrible job to DIY, but a lift would certainly make the job a piece of cake. What tune did you decide to go with, or which one comes with? I'm also curious when you pull your TCU if you see any signs of oil. Make sure to change that 13 pin connector while you're at it as a "while your in there" and forget about it type deal.
Joe, that's great! Glad it's exceeding expectations. Hopefully I'll feel the same! I'll probably stick with the stock TCU I got from them in November and I'm having the valve body swap done at MAG Motors over in Cleveland along with a long list of other tasks I'm sure they'll enjoy beating the hell out of my wallet doing. They're a Benz only shop with an owner who boasts the highest certification that MB awards, and both he and his lead mechanic are S Class owners (mechanic an S55) so things tend to get done right.
'06 MB S55 AMG; '04 Audi Allroad 4.2; '05 BMW M3 Conv.; '92 MB 500E
Originally Posted by CICBarkeep
Joe, that's great! Glad it's exceeding expectations. Hopefully I'll feel the same! I'll probably stick with the stock TCU I got from them in November and I'm having the valve body swap done at MAG Motors over in Cleveland along with a long list of other tasks I'm sure they'll enjoy beating the hell out of my wallet doing. They're a Benz only shop with an owner who boasts the highest certification that MB awards, and both he and his lead mechanic are S Class owners (mechanic an S55) so things tend to get done right.
Not to be a cooler, but they're not the ones who overfilled the transmission fluid are they?
Not to be a cooler, but they're not the ones who overfilled the transmission fluid are they?
maw
lol....to this point i will say, after the trans service/fluid flush I've noticed the +/- 1 Gallon of ATF FCP included in the kit doesn't appear to be enough to fill it. I just ordered 2 more Liters to top it off. Granted I'm measuring using the Chinese Ebay special Transmission dip stick which is 2 feet too long, but when its running i'm gettin a reading of just above the low line on the bottom of the stick.
I don't want to over fill so hopefully im going about it correctly. I'll add little by little and keep adding to get it just right. not sure whats worse, undefiled or overfilled
- Joe
Last edited by PHILLYCLSJOE; Mar 19, 2025 at 07:19 PM.
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