My 01 has for the past 6 months or so intermittantly set off the limp mode when pulling a heavy load (10-16 thousand pounds) I took it to the dealer and he couldn't find the cause the first time, but now I took it back again and he say's the whole filter, housing and all needs to be replaced. I haven't been on the site in a while and a search didn't reveal much, but is this something that has been going on with these trucks? How can the housing fail? BTW, they quoted about 6-7 hundred for the part. Dang???