FEI,I installed a Blue Box on my 1999 dooley about 8 months ago and have had no problems at all. It is programable, with 3 settings;15%,50%, or 60% more fuel. Since I pull a 8500# boat only about 3 times a year, I leave it on 15%,which is about 300HP according to the Blue Chip people. They said that on the 15% setting that no other mod's were req'd. They used that setting on their test truck, and all temps and pressures were well within factory limits. My truck is an auto dooley w/ 4. 10 rears. Mileage the same with or without box on, about 15 in town,17 on road empty. Towing boat to river,got around 11. 5 at 70-75 mph on cruise. Never lost more than 5-6 mph on any of the hills from Hartford Ct to Newburyport Ma. , and there are some long somewhat long pulls, temp stayed just below 190 entire trip(115 miles),air temp 85. If you use the higher settings, Blue Chip recommends transmission and/or turbo mods,depending on load weight etc. Also can be turned on off at any time. So far as I am concerned, it's a hard product to beat.
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