Has anyone else had a clunk in the engine just moments after startup? My new truck does it every now and then and my 07 did it as well. Sounds almost like a PTO being kicked on under load. Just wondering if its happening to anyone else?

 

Should also mention this only happens when truck is cold and hasn't been ran for 24hrs or more.

 

Sounds like an AC compressor, I've heard them make noise like that before. I believe its pretty common too...

 

Was thinking that myself, its super annoying and doesn't sound at all good

 

A/C compressor engaging. You would think they would be able to control it better but it slams right into action. It sounds terrible but my 04.5 did the same thing and it never crapped out. I try to shut my a/c off each time I shut the truck down but sometimes I forget and it reminds me with that nice noise.

 

Yup, its the a/c. For awhile I thought something was seriously wrong. Only seems to be a issue the first time it engages though.

 

Turn off A/C and or defrost before shutting down, seems to help mine

 

Thanks guys, I had a hunch it was but I always forget to turn it off after i shut the truck down