I have been a long term member of another site and read a lot on this forum, but this is my first post. I posted this topic yesterday there and they deleted it, made me mad, and I moved over here.

I have been having a problem with my truck loosing coolant while hauling a large load (pulling my RV or hunting truck on a flat bed trailer). I smell coolant in the cab from time to time during the load, but do not see any signs of leaking around the bottle. I do not see signs of leaking on the ground. The coolant temp, according to the Attitude is around 190-200. My boost is around 20-25psi going up hill (never more). My EGT is 700-1050 but never more than that. I changed the EGR and bottle cap, but still have the same problem. During my last haul, I unplugged my EGR and the problem when completely away. I drove about 100 miles with it unplugged and did not have any lose of smell any coolant. I plugged it back in and started smelling it again.

I am running an Edge Plat with Attitude, turbo back 4" exhaust, and stock air filter. I normally see boost pressure of around 25psi during a big haul on level 2. I have tried removing the Edge, setting it to level 1 or 0, but still have the same coolant lose. I do not see white smoke like head gasket people will see, and I do not have issues with the EGR plugged in during normal driving. I have about 63K miles on it and never had any other issues.

Why would unplugging the EGR fix the problem?
Why do I see a 5 psi boost drop with the EGR unplugged?
What could be wrong that unplugging the EGR fixed the issue?

Like I said, I read a lot on this formum and thought the EGR valve and/or the bottle cap might be the issue, but they are not because both have been replaced.

Any help is much appreciated.