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My truck is a 1999 5 speed 24V 4x4 dually. I do not have any problems starting and no problems with it dying. I have replaced the injector pump, lift pump, ECM, TPS, fuel relay, and fuel and air filters all within the last 16 months. The injector pump was replaced again in February 2015 due to an o-ring blowing out. These problems started after that pump replacement. Truck runs fine while it is cold, but once it starts to warm up it seems like it falls on its face for a second while I am driving. When it first started happening it would do it when I tried to exceed 60 mph. I tried to get it to act up while I was parked and it did not for quite a few days and then finally it started acting up while I was parked and throttling up to about 2100 rpm. Now it does it at 50 mph and about 1100 to 1300 rpm. The engine is not dying, it simply drops a couple of hundred rpm for a second and then picks itself back up. It is starting to do it more often the warmer the engine gets. I have had the truck to two shops, both guys are certified cummins mechanics with over 20 years in the business, and I have had it to one dealership. The two independent guys say they can not figure it out and it drives them crazy. The dealership called about 3:30 on a Thursday afternoon asking for patience while they figure it out, "we don't want to just throw parts at it, we want to get it right". About 8:30 Friday morning they call back and say "we can replace the injector pump and ECM and see if that fixes it, using Chrysler parts that will be $6,400.00". The truck has been pretty much down since February, I would like to get it on the road again, any ideas? The truck only has 187,xxx miles on it.