I have a 2016 A8 that had the transmission problem and so I did the triple flush and bought the range device. My car still every now and then the RPM's sometimes go up without me doing it. Would a tune that disabled the AFM be better than the range for that, would a tune eliminate the RPM surge?

 

Diablo I3 tune, turn off the AFM.

The correct way to turn off the AFM is thru a tune inside the ECM, not by tricking the ECM with a Range.

 

Thanks for the help.

 

Do you think the Range is a waste of time. I hate to spend $200+ and then find out that it was a waste of time.

Dave

 

It stopped the V8 to V4 change but I do get RPM surges every now and then.

 

For an A8 I think its worth it unless you drive in manual mode most of the time (in manual mode it will not switch to 4 cyc so no need for it). Plenty of reviews says it works as intended. Also everyone suggests buying directly from Range to ensure you get the latest software updates (previous versions would slowly drain your battery).

 

If your only concern is eliminating AFM, a tune will not do anything more than a Range unit. The only difference between the two methods is that the tune, if detected, will void your warranty. The Range unit won't. It sounds to me that you have one of two conditions: 1. You haven't allowed the new fluid enough time to take effect (I was told 200 miles or so) or 2: You waited too long to have the flush performed and suffered irreversible damage to your internals. If that's the case I would advise you not to tune your engine. Your drive train warranty may become very useful to you in the near future.

 

I have only had my car for a month so I am guessing the internals may be damaged. But I am still under the 200 miles since I had it changed. The car did only have 3500 miles when I bought it.

 

I have only had my 2016 A8 for a few months and it only has 9800 miles on it . How soon should I get the triple flush? I think I'm going to go for the Range unit.

Dave

 

P.S. No matter what method you decide to use, get rid of the AFM. My research has convinced me that the Torque Tube, unlike the traditional heavy drive shaft, cannot withstand the effects of the AFM transitions long term. It leads to clutch failure but also causes long term damage to the bottom end of your engine. I'm not much for straying from OEM design but after doing a little leg work I was convinced that eliminating AFM was the way to go. I advise you to do some detective work and then decide what's right for you.

 

Let your warranty status/wallet be your guide. I just had mine done under warranty but was told that the process would cost over $700 without it. Honestly, I didn't think I had a problem and had the process done more as a preemptive measure. I noticed a positive difference as soon as I left the dealership. The shifting was definitely crisper and smoother. Moving in and out of gear was a very soft/smooth transition. Definitely worth the effort.

 

Thanks !

Dave

 

Diablo will not void your warranty if you flash it back to stock.

No CVN change or other foot prints left behind.

Just contact Diablo for the true story.

 

^^ This! I voided my warranty Day-2 with a good tune (+intake, headers, xpipe); however, my engine builder has my back. If you're not going to further mod your car, Range 100%.

 

I've installed Diablo tunes (Diablew was my tuner) in all my GMC trucks since 2014. I know the product and it works very well. We can debate whether or not the tune is detectable until the cows come home. But in the final analysis, if your only goal is to get rid of AFM why risk losing your warranty with a tune when the Range unit is certain not to be detected?

 

Some good advice in this thread.
I've owned two C7 with A8, a 2016 Z51. It started the shudder at under 1000miles. At that time dealers were told to change the TC. That worked for a while but at about 7k miles shudder started again. Had the triple flush and that seemed to work. The RPM thing I think is caused by AFM system shifting to 4cyl. I had a range device but only used it about a month- it caused a code related to transmission communication so I removed it.
I just got a 2017 GS with A8. I checked with the dealer and the triple flush was performed back in late 2019. I abolutely hate driving a sports car that can not decide to be an 8cyl or a 4cyl? Plus I think the AFM system confuses the transmission and thus we get weird rough shifts at times? So I got a new Range device and its been working fine. No switching back and forth between 8 and 4 Cyl? It seems to run much better.

The Bad Transmission fluid issue has been frustrurating and interesting. A GM tech described it to me as the old fluid absorbed mositure which cause the viscosity to change thus causing the TC to struggle doing its job? It sounds reasonable, but I wonder if the Shudder happens more in high humidity areas vs very dry climates?? The transmission is a sealed system, but even sealed systems can have condensation. Regardless some small group of GM folks know the real truth, and they have figured out that changing to a new transmission fluid fixes the problem. I wish this same group was smart enough to know that 90% of Corvette owners(my guess) hate having a system that goes from 8cyl working to 4cyl kinda working without any owner control. If they just added a on/off switch for the AFM they could call it MFM and there would be so many happy owners and likely lesss complaints about other stuff?

 

Still under warranty, so I went with a Range. It works as advertised and when it goes to the dealer, unplug it and leave it home.

 

Yep, the Range device works very well in keeping the car out of 4 cyl mode. To me it was worth the price.

 

I have used the range device and it was ok but the older version would sometimes run the battery down or throw codes, I had it updated but never used it again, instead I went with the Diablo tuner and tuned out AFM and put in the tune for 93 octane only even when my car was still under warranty, took it to the dealer for warranty a few times and also asked them to do the triple flush last year with the new blue label fluid as a precaution and they did that also with no questions asked, I would put the original tune back before I took it in and never had a problem. it is now out of warranty so it doesn't matter,

 

With Diablo do you have RPM flare?