No news on the PCV yet.
Yeah I didn’t think about that if it’s the same gear lash then odds on it won’t change !
Just thought it might be a solution, an expensive one I know. If it’s not going to change the issue I’m having then unless it’s 100% I don’t think I’ll take that route to be honest.
I know you have been busy with other projects but where are you at with the PCV blanking kit any closer to having it completed or no closer than the last time i asked you ?
Come on son I’m gagging to get this on my car !! 
If I was in your position Steve, I’d be asking myself if the LWFW gives enough performance increase to justify the chattering and living with the annoyance.
I know my answer would involve fitting the OE flex plate if its a daily driver, I simply wouldn’t tolerate that.
I know what your saying James and it might be the case if I can’t get it better than it is now. Everything I’ve done to the transmission and clutches so far has improved the issue each time so there’s hope yet !
I do love the way it’s made the car feel it makes the engine spin up so fast now and things just seem more fluid with the up shifts and down shifts of the transmission so I’m torn at this time, the car also is running ace atm it’s only in traffic the problem becomes annoying.
The actual flex plate is not the problem as far as I’m aware it’s the flywheel. I have got a brand new RS5 flex plate sitting in a box in the garage so if needs be I can put it on !
I’m not giving up yet I’ve got a few people on the case so we will see and if after this I can not live with it I’ll change it back to the oem flywheel … well maybe lol 
Wow, Steve et al, I missed all of this…thanks for everyone’s efforts, hopefully we can find a solutions in the near future🤞
Incidentally, my rear differential failed a few weeks ago…and was replaced under warranty thank you universe!!! I am not sure what caused the failure…Audi changed the fluids as part of my 75k service that I had done at 60k and when I got the car back my differential warning light came on. I brought it back to them and they realized that there was an air bubble in the line. They replaced the fluids again and a couple of weeks later I started hearing a noise and the rest is history. Not sure if that was the cause or just coincidence?
When I got the car back it seemed as if the juddering significantly decreased. But now that I’ve had it for 10days ish I think the improvement is slight…or maybe not at all, it’s hard to say. The wheel jerking only seems to happen on the front two wheels during the juddering episodes, which seems to support Michel’s research suggesting the front open deferential issue.
I have definitely enjoyed the improvements that the lwfw have added and can “tolerate” the judder, but if I ever wanted to sell the car, prob never, but if I did, it would certainly lessen its value. It is also a little embarrassing when it starts that loud rattling as I am pulling in or out of a parking lot….and annoying when I pull into my home garage…and just frustrating that my car isn’t running optimally and that it happens to be my car that is this anomaly (and Steve’s of course),
I may/may not get the JHM headers with high- flow cats after I pass my emissions test this August and, if so, I am thinking about taking the 15 hour drive to JHM and have them see if they can figure out the judder and noise when they perform the header install. Per Michel’s note and the back and forth with Steve, it may be that these two cars have funky front open differentials? Michel, did you happen to run your theory by Jake? If not, I can shoot him another email as we haven’t heard anything from him recently.
Hey Adam,
Glad you have caught up on things on here there are some interesting possible reasons why we are having this issue. I do think Michel is on to something with the gear slop in the front diff.
What we need to know or workout now is if there is a solution or a way we can maybe trick our cars via the TCU or ECU or even doing something mechanical so we can at least reduce the effects we are experiencing or totally eliminate them if that’s possible !!
Sorry to hear about your diff I am certain that Audi messed your service up causing a starvation of oil and that caused the diff to give up on you. If it was me I’d be asking them to pay for the lot !!
Hey Steve,
Let me know what you think next steps are…another email to jhm with Michel’s thoughts?
As far as Audi shop, fortunately it cost me $250.00 to replace differential and I figured that it might be tough to definitively prove that they are at fault without a big fight and possible exposure to the fact that my car is modified…so I just covered it, choosing the path of least resistance this time😉
Let me know how I can support efforts to remedy judder.
Thanks!
I agree with Steve that it sounds like the dealers fault. Not sure what they meant by an air bubble in the system? But I also agree with you that for $250 I would keep my mouth shut if I could walk away with a new T.V. rear diff for $250.
Yeah, they might have been b.s. ing me on the air bubble statement….maybe they left it bone dry…
Yes I agree 250.00 is nothing for a new diff I probably would of done the same as it could of been a big hassle if they knew it was a modified car, good choice👍
I think another email would be good to JHM as we have not had anything back from them as to what they think the cause is ?
I would maybe hold fire on Michel’s thoughts and let’s see what they come back with first !
It will be interesting to see what there own thoughts are on this issue !!
Ask them about the supercharger while your at it ahha
Will do @steve and lol and will do @mblais and hopefully we won’t be waiting in vain for a response…the squeaky wheel gets oiled?
Hey so I didn’t get a chance to read all 92 comments but just wanted to throw this out some info I received from a conversation I had on AZ when installing my Crank… I’m in a 2011 S5 4.2l and had the crank upgrade and ever since I’ve had a slight vibration which I told myself I knew would happen but just trusted that the engineers at JHM would have had it perfect so I lied to myself and went for it. Of course now I have a vibration. Not bad and not like the judder that is shown by the 2 commenters with the videos towards rh beginning. Mines way different and to me it’s got to just be a balance thing after dropping that much weight and all the moving around and vibrating its gone through in its life just rolling over 100k. Either way bothers the F out of me because I dont want it turning into a runaway catastrophe and have engine parts all over the road . Anyone else hear of such vibration? I also have an APR stage 1 tune and speaking of I’ve had it with APR. Thier customer service over the past 2 months has completely bturned me away from the brand. I’ve emailed them nearly 10 times asking specifically if I need to have my tune adjusted because if the massive weight loss and the fact that the motor is turning over so quickly now , no where near as it was previously. All I’ve received is a copy paste email asking for my car specifics which I had clearly already provided previously so I can’t get any damn answers and yeah I should just call but at this point it’s literally the principal of the damn thing idk… but moving on the real reason for this comment, when asking people about this vibration in AZ there was a guy that had installed one on his rs5 and he too was running an APR tune and his motor was just running like shit. Never saw a video but I imagine very similar to the videos at the beginning here. After spending fuck tons of money diagnosing and making calls and this and that it turned out it was his tune. The APR tune will not jive up with the way that crank is now able to spin. Essentially it was spinning to damn fast and with the RS5 specifically . So idk what tunes you do or don’t have but he was adamant that you cannot run an APR tune with the light weight pulley from JHM. Just a heads up and if someone has already discussed that then I guess I’m just here to reaffirm these findings. Hope you guys get it sorted… I almost cried watching those motors shake like that… like watching a crackhead detox cold turkey with them shakes. And if anyone else has a small vibration or heard of it lmk. I’ve yet to locate anyone else with this mod but the one rs5 guy on AZ so I’m just shootn in the dark with my guesses as far as it being out of sync with the heavy weight loss.
I just installed the JHM lightweight Crank shaft pulley and Alternator pulley today but haven’t driven the car yet. But I do have the JHM Lightweight Aluminum JHM flywheel along with the JHM Stg2 tune, the tune I’m running is customized to the lightweight flywheel along with and SAI & Cat delete. I can say that there were a little more vibrations but not very noticeable, mostly at idle obviously. I don’t imagine that the install of the Lightweight Crank/Alt pulley will make much of a change.
Hey there, I am the guy who posted the pics of my car juddering.
JHM did get me and the other person, Steve, an updated tune that almost entirely eliminated the judder. The cold start is now dramatically different and does this “mini short rev” thing, and the idle is at a higher rpm. I believe that they are still working on some tweaks to get to the bottom of it all, but I am glad that the judder is (almost) gone.
I don’t know if this info is helpful to you, but I figured I would share this update…
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Hey Adam,
I been following you and @SteveRS4’s posts about the judder. I am considering the JHM LWFW, at the same time a brand new transmission unit, down the line for my B8 RS4, since I had some prior mechanical issues with my transmission that would be difficult to resolve. Installing the new trans unit would also be a good time to install the LWFW I presume.
I spoke to @Ape_Factory about this and he said that, with the latest JHM Stage 2 ECU + TCU remap, there should be close to no judder? Would you be able to share some more of your experience with this?
FYI I did the remap sometime around July 2021, and it’s on a B8 RS4.
Thanks and looking forward to hearing from you.
Just to clarify, most don’t have the noise after installation. If you do, and it’s severe, the tune can be modified near idle a bit to help.
I had the same issue as you say I had everything replaced in the transmission ie K1 & K2 clutches
a new mechatronic unit oils, filters, gaskits etc all OE parts. This did make the judder a lot lot better but it was still there slightly.
In the end JHM have been amazing trying to eradicate this issue after sometime the idle was turned up to just under a 1000rpm and it has made the judder disappear !
There is a very slight what I’d call a wobble its not felt at all like it was before but I do hear it as if the engine as pulling away has the slightest wobble to make the exhaust shake but its very very slight and almost unnoticeable 99% of the time.
I hope this helps, if it was me id still have the LWFW installed as there is ways around the problem thats if you get the problem in the first place as id say 98% of people don’t seem to be effected !!
Thanks @SteveRS4! That is useful information.
Since you said 98% of people don’t seem to be affected by this judder, does that mean they have a perfectly normal functioning gearbox, without judder? What about chatter at idle? Any other NVH i should be aware of?
Would you say it is good enough for a daily driver?
Yes its ok as a daily driver no issue as I use mine most days.
I’m not sure what causes the judder to be honest some say its gearlash and the tolerances are not as tight as others.
I know our RS4’s are lighter than the RS5’s i say that because mine seem to sometimes stutter and splutter went pulling away at a juction almost like it was over fueling its self and bogging down it was a bit dangerous at times if you needed to be quick.
Also if I was on a hill in reverse and holding it on the throttle then letting off slightly it would almost disengage the clutch and the car would roll forward as soon as you added the throttle again it would grip up and hold it ?
But since having the idle turned up it now does not do any of this and acts totally normal it holds on hills with no throttle input and as soon as you touch the throttle it moves away cleanly.
Infact its easyer and smoother to drive in general and pulls away perfectly and goes like a bat out of hell.
So to me its like the lightness of the flywheel struggled with the low RPM with the car maybe being that little lighter ? I also felt when I had passengers in the car it did not struggle as much with these symptoms !
Thats my feeling and what I think but that doesn’t mean anything or maybe makes no sense but thats how it felt …who knows 🤷
There is slight chatter when in park but hardly anything and no NVH at all.