I answered these questions myself...and GDE isn't doing the tune anymore and on U.S. vehicles
A regen is short for regeneration. There is a big filter in the exhaust to collect particles of soot. This eventually gets filled up and if let fill too long would create a restriction--think of a clogged air filter, but on the exhaust side. Instead of changing the (very expensive) filter every few hundred miles, the truck self-cleans the filter by dumping unburnt diesel into the exhaust. This burns in the filter and gets hot enough to turn the trapped soot into ash which blows out with the exhaust. This all happens automatically and usually without the driver being aware.
This is a good answer about the "Exhaust Regeneration in Progress" notification. I NEVER had this until they did the "modification". I then got this alert about 4 times until "exhaust filter almost full"...then more "regen" alerts finally "Exhaust Filter full" alert. Dealer CHARGED ME $140 to "burn out the filter". All good for 3 months and started again. This time it is accompanied by "EGR slow to respond". More "Regen" alerts etc. EGR valve is "on order" (5 weeks now) and will be covered by warranty.
Supposed to be very similar to previous versions, just not touching the EGR function. I would suggest if you have FB account is to follow them on there.Interesting.....What might this tune do for us?
Good oneA regen is short for regeneration. There is a big filter in the exhaust to collect particles of soot. This eventually gets filled up and if let fill too long would create a restriction--think of a clogged air filter, but on the exhaust side. Instead of changing the (very expensive) filter every few hundred miles, the truck self-cleans the filter by dumping unburnt diesel into the exhaust. This burns in the filter and gets hot enough to turn the trapped soot into ash which blows out with the exhaust. This all happens automatically and usually without the driver being aware and you can get the best RV reviews here from Go RVing reviews.
The GDE tune was a very good one, but unfortunately isn't available at the moment in the states thanks to overreaching by the EPA. Lobby your representatives to pass the RPM Act of 2019.