[daryl rsv4]

Not what I wanted to hear but that was the diagnosis of my 14’ 435 Msport yesterday at SSR. Car has stage 2 bootmod, VRSF catless down pipe & VRSF chargepipe. Car has been tuned since 18k, now has 54k. I do not beat on my car and am pretty good about routine maintenance (oil changes every 3k). I have had an O2 sensor that has been bad for the last 6 months that I have neglected, but the reason I made the appointment at SSR along with changing my spark plugs. I have experienced bogging, sluggishness at times but attributed it to the O2 sensor and plugs. I have to take the day off of work when I make the 50 mile drive to SSR as is typically an all day affair (with traffic to and from).

Transmission code present for slipping. Damn. Used transmission (3 month warranty) + labor + O2 sensor (couldn’t get one yesterday) =$3500.

Thoughts?

[n55david]

whats the code for slipping?

[daryl rsv4]

I’m looking at my invoice and it doesn’t state the codes. He (tech) showed me on his hand held and I don’t remember. I just texted him to ask specifically what codes they were.

[5soko]

I wonder if bm3 uses tq scaling on their tune only option, and also wonder if their tcu tune is scaling just ecu tq or an a actual tcu tune

[ctt300]

Does it feel like it’s slipping, do rpms jump? I highly recommend a second or even a third option in cases like this. I wouldn’t trust that diagnosis. These transmissions are very stout and can take quite the beating. Guys track their cars without issue.

Bogging down isn’t generally going to be a trans issue, but surely an engine issue, like maybe bad plugs, replace those if haven’t already. Do you have the stock air box or another cone filter deal?

Replace the bad O2 sensor, clear codes and drive to see if you still feel the bogging issue. When is that occurring -any more details?

[thejeremyman9]

Originally Posted by 5soko

I wonder if bm3 uses tq scaling on their tune only option, and also wonder if their tcu tune is scaling just ecu tq or an a actual tcu tune

This was my first thought - wondering if he had micro slip in 3rd/6th and after running the tune for a decent amount of time, just wore out the trans.

Also agree with other posts that you should fix the known issues, clear all codes, and try driving the car a bit more.

[daryl rsv4]

Originally Posted by ctt300

Does it feel like it’s slipping, do rpms jump? I highly recommend a second or even a third option in cases like this. I wouldn’t trust that diagnosis. These transmissions are very stout and can take quite the beating. Guys track their cars without issue.

Bogging down isn’t generally going to be a trans issue, but surely an engine issue, like maybe bad plugs, replace those if haven’t already. Do you have the stock air box or another cone filter deal?

Replace the bad O2 sensor, clear codes and drive to see if you still feel the bogging issue. When is that occurring -any more details?

It sometimes feels clunky. If I stop at a stop sign and then try and accelerate it will have no power. For whatever reason, whenever I turn left
(I’m assuming because im off the gas) and then try accelerate, it’s clunky with no power. The other night I was entering a downhill right hand on ramp onto the fwy, (the same one I take every night) going home from work, and usually by the time I get to the bottom and entering the fwy, it feels like I’m in 8th gear and the car has no power, so I have to get off the gas and get back on. This particular night, i get off the gas and get back on, and the car accelerates but the rpm’s stay high (5.5k +) and don’t back down, so I hit the gas again to try kick the rpms down and they stay high. I then got a drivetrain malfunction message on my display. I let the car decelerate and the rpms stay up so I get off on the next exit and pull over, put in park and turn the car off and let sit for few mins. Start the car and everything seems back to normal.

Again, I attributed everything to the 02 sensor/ plugs until I got the drivetrain malfunction message. I did have my plugs changed when I was at SSR on Friday. I have the stock air box btw.

I appreciate everyone’s input..

[ctt300]

Originally Posted by daryl rsv4

It sometimes feels clunky. If I stop at a stop sign and then try and accelerate it will have no power.

This particular night, i get off the gas and get back on, and the car accelerates but the rpm’s stay high (5.5k +) and don’t back down, so I hit the gas again to try kick the rpms down and they stay high. .

Yeah, that sound def like trans slipping? Did you just buy this car? Is it from a big dealer or private person? I’d be telling them something..

[daryl rsv4]

Originally Posted by ctt300

Yeah, that sound def like trans slipping? Did you just buy this car? Is it from a big dealer or private person? I’d be telling them something..

No, I have had the car since Jan 17’. Picked it up as a CPO w/ 14k..

[thejeremyman9]

Originally Posted by daryl rsv4

No, I have had the car since Jan 17’. Picked it up as a CPO w/ 14k..

Are you Xdrive and how often have you launched it?

[ctt300]

Originally Posted by daryl rsv4

No, I have had the car since Jan 17’. Picked it up as a CPO w/ 14k..

Try getting a goodwill repair from BMW NA since it’s at what 65K miles now?

[daryl rsv4]

Originally Posted by thejeremyman9

Are you Xdrive and how often have you launched it?

No, rwd..

[daryl rsv4]

Originally Posted by ctt300

Try getting a goodwill repair from BMW NA since it’s at what 65K miles now?

What’s a goodwill repair? I’m at 54k..

[ctt300]

Originally Posted by daryl rsv4

What’s a goodwill repair? I’m at 54k..

Goodwill repair in the warranty world is repairing or reimbusing for repair just outside the warranty window of time/miles. BMW and other manufacturers will take care of failure costs when this occurs. They do advertise their lifetime transmission fluid life, so I'd stick em' to it.


You have nothing to lose ad it is only fair that this is covered by them.

[daryl rsv4]

End of last summer when I took it to the local BMW dealer for my radiator fan, they covered it as it is a CPO. That’s right when I got the CEL (O2 sensor) and they wouldn’t touch it because of the tune. I highly doubt they’ll do anything about the transmission..

[ctt300]

Originally Posted by daryl rsv4

End of last summer when I took it to the local BMW dealer for my radiator fan, they covered it as it is a CPO. That’s right when I got the CEL (O2 sensor) and they wouldn’t touch it because of the tune. I highly doubt they’ll do anything about the transmission..

Ha, tell them that the manufacturer has to prove that the mod caused the failure per the Magnuson-Moss Warranty Act. Be prepared to contact an attorney to fight for your rights though...

https://en.wikipedia.org/wiki/Magnus...s_Warranty_Act

[harkes]

Magnuson-Moss bla bla bla... Who in here is ready to face BMW Corp in court if they dont want to comply. Hardly anyone I'd think - and BMW (and any other car manufacturer) knows this. In real life that Warranty Act isn't worth anything - sadly.

[Poochie]

Originally Posted by ctt300

Ha, tell them that the manufacturer has to prove that the mod caused the failure per the Magnuson-Moss Warranty Act. Be prepared to contact an attorney to fight for your rights though...

https://en.wikipedia.org/wiki/Magnus...s_Warranty_Act

It's cute how that Magnuson-Moss Warranty Act always gets thrown around here, like it's gonna magically make a dealer shake in their boots and give in to any of your unjustifiable demands.

Are your pockets deeper than BMWs? If not, then threatening them with meaningless nonsense, like Magnusson Moss, is as effective as praying..

[Korvo]

This forum should have an "autobahn" feature for anyone that mentions Magnuson-Moss.

[thejeremyman9]

One other thing not mentioned yet here, if you really think the trans is bad anyways, is you could try flash XHP and see if it makes a difference.

Other than that, you can try the goodwill warranty route, as it does hurt to ask. A friend of mine got his motorcycle engine covered under that (parts only) when it dropped a valve about 300 miles outside of warranty during normal driving (he had video to prove it). Maybe try a different dealer you didnt go to with the tune? (Did you actually go in with the tune still on, or did you remove and flash back to stock and they detected it anyways?)

[daryl rsv4]

I went in with the tune as my radiator fan took a shit in 90-100 degree So Cal weather and needed to get in ASAP and didn’t get a chance to flash back to stock.

I’m going to get another opinion/ estimate today.

What would be the better option, rebuild or swap with a used trans?

[daryl rsv4]

The codes were 4204C-1 gear ratio monitoring in fixed gear, clutches C &D disrupted.