I've seen a lot of discussion but I haven't been able to find the actual definitive changes made to the exhaust between model years. I know the 2021 was much quieter but was it just the ECU programming or did something physically change? What about the 2020 vs 2019? 2018? 2017? I have heard people say their 2019 was louder than their 2020 but this is just anecdotal and I'm looking for a technical explanation. The only reference I have is a 2014 which was insanely loud at any RPMs.

 

GPF was fitted around MY19, I believe, which would quieten things down a bit. The tune does the rest of the adjustment, presumably for all MYs.

 

I've been told by multiple dealers that there was no GPF in the US. This is what I mean when I say I can't get a clear answer. Are you talking about European cars?

 

My understanding of it for North American cars, from the factory:

MY13-MY18 - loudest and most unrestricted
MY19-MY21 - software patch that removed driving mode memory and quieted exhaust
MY22-MY-23 - GPF added, quieter still

Software patch was retroactively applied during dealer visits to many MY18 and earlier cars to make them quieter. The MY22+ in the US definitely have GPF embedded in the cats, as JLR decided to have only one global configuration instead of one for UK/Europe, one for the US, etc., as GPF was required in the UK since MY19.

 

Okay so how were MY19-MY21 cars quieted? Did the software just make the car forget the driving mode for a quieter startup or was something else changed to make it quieter while driving.? If so do you know what that was? Can this be completely changed back to 2018 and before with a VAP tune?

Okay so cars in Europe got the GPF for MY19 (exact VIN split is end of 2018 calendar year) and then US ones got it later. This would explain the new one I test drove but I've also heard 2021s in the US that seemed much quieter than 2019s. It's confusing.

 

The GPFs may have started to get installed mid-MY21. JLR is famous for making changes during MYs instead of between MYs like most manufacturers.

The software's main function was to make the cars forget Dynamic mode so start-ups were quieter. I believe many reported that the RPM threshold for opening the valves was also raised to also keep the car quieter in Normal mode.

 

Sorry for being dense but what does GPF stand for?

 

Gasoline Particulate Filter AKA Otto Particulate Filter (OPF).
Seeing as the Diesel Particulate Filter (DPF) has been around for yonks and the gubermint decided that gas/petrol engines also put out enough particulates to require a filter (they don't).

 

Yeah I mean the main complaint in reviews of the 21' facelift was the lack of sound so I still think it was more than software. It's a massive difference.

 

The software patch was applied to my MY18 FTR and it removed the the driving mode memory in my car. My car is a little quieter at lower RPM, but I can't really notice much of a volume difference above 2K, so all in all it wasn't as disappointing as I anticipated it to be.

 

Can you tell me what the software campaign code was for that update?

 

H136 - Pass by Noise in Latched Special Programs Mode

 

Also K309...I believe they are the same but referenced by different numbers.

 

I had a 2016 and currently have a 2018. Both are loud and have all the pops/crackles. My dad had a 2020 and it was just as loud starting up but it didn't pop/crackle as much.

 

I think this is the answer. Kinda crazy this isn't known on a forum dedicated to the car so it must depend on software version as well. I just drove 500 miles to test drive a 2019 svr because I thought that was old enough and it didn't crackle at all. Tons of anticipation when you let off and then...nothing.