Yup, mine does this too. Haven't been to the dealer about it, but I might now.

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Blue 2008 Tundra SR5 dbl. cab 4X4
5.7L I-force V8 engine
Michelin LTX A/S P275/65R18 tires
Towing package
TRD rear sway bar
OEM heated tow mirrors
OEM brushed stainless steel running boards
OEM bed extender
OEM bed rail system
Line-X bed liner
POD electronic trailer brake controller
XM RoadyXT satellite radio
Clarion and Boston Acoustics speakers
ZX 350-4 Kicker amp
ZX 150.2 Kicker subwoofer amp
Bazooka subwoofer
Cobra 29 LTD Classic tweaked and peaked CB radio
Wilson magnetic CB antenna
Thule 822 bed-rider bike rack
Du Ha under seat storage system