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30k service on my 07


Full Member
Sep 21, 2006
Almost 30k, 29959.....I changed the front and rear diff oil myself.? Put valvoline 80 90 synth blend in the front (piece of cake).? Used Mobil 1 75 90 full synth in the back (pita).? Having to syphon the old fluid out was not much fun.? Is it too much to ask for separate drain and fill plugs on a rear diff?? I also noticed my rear diff cover was almost completely rusted and most of the paint has flaked off.? Anyone else notice this on their 07?? I asked the dealer about it and they claimed that it was the result of my driving 2 days in the snow and salt covered roads this past winter.? They also pointed out my driveshaft and various suspension components were completely rusted over, again, blamed it on the salt.? Should I worry?? I also had the same dealer service the transfer case and transmission.? They did a BG flush on the tranny.? I was a bit worried at first, but, man, what an improvement in shifting, it's quiet and smooth again.? Hope it lasts.
Reason for no drain on Diffy is 2 fold...IMO

A not required to change it per manual for long long time....
2 possible low leak point or something that can get knocked off while offroad
That just makes me feel better that I'm very close to 16k on my 2007 right now (will be guaranteed to go over 17,500 before it's 1 year birthday in July too!).  As far as rust goes, I haven't paid any attention to the driveshaft or other such.  Maybe I should look closer though.  I did get to drive in a bit of slush and a LOT of briny wet roads this past winter!
Yep.  Rust on the whole length of the driveshaft, and some on the differential cover.  The cover appears to have been painted black, but the rust underneath the paint has caused a couple quarter-sized spots of the paint to flake off.
I drive @4k a month, mostly for work.? Glad it's a company truck!? Lucky too!
I'm glad I'm not the only "rusty" one.? USA1fan, if you ever get a chance to ask your dealer about it, let me know what their take is.? A coworker of mine also has an 07 Avy and his rear diff cover is rusting too.? I've never noticed any excessive rust on other vehicles I've owned and driven in the snow, but I've never really looked for it either.