Recently I was pulling a long grade with the camper on and boat in tow w/
a gross wt of 16,920 lbs. I had the Edge set in lvl 2 and was doing about
65mph in 5th gear. I was in the desert and it was around 95 on the mirror.
It was running fine around 208 degrees and the SES engine symbol lights up.
I get on Onstar and they run they diagnostic the operator tells me it's a EGR
code and I should have it checked within 7 days. I asked for the code number but she didn't have it. I plowed on over the grade and everything was fine. I stopped for fuel and shut her down and when I restarted the SES light was off.
My question is should I be concerned about this? Has this happened to any of you guys? I might add that this truck is catless........

Recently I was pulling a long grade with the camper on and boat in tow w/
a gross wt of 16,920 lbs. I had the Edge set in lvl 2 and was doing about
65mph in 5th gear. I was in the desert and it was around 95 on the mirror.
It was running fine around 208 degrees and the SES engine symbol lights up.
I get on Onstar and they run they diagnostic the operator tells me it's a EGR
code and I should have it checked within 7 days. I asked for the code number but she didn't have it. I plowed on over the grade and everything was fine. I stopped for fuel and shut her down and when I restarted the SES light was off.
My question is should I be concerned about this? Has this happened to any of you guys? I might add that this truck is catless........
This happened to me on my 01 pulling a 4000 lbs. trailer up steep grades. once leveled out, ses light turned off. I was told it may have had to do will my mass air flow sensor being dirty. I cleaned and reoiled my K&N and cleaned the sensor and it has never happened since.

When you modify the exhaust on the LB7 you will set 1 of 2 EGR codes, normal with the aftermerket upgrades