[bentol888]

I went in for an oil change and wound up getting my tranny and rear diff replaced as well at 40,000. Then I get home and get on line and see that I might have jumped the gun and not needed them at all. Also the mechanic said my spark plugs needed replacing as well. What gives? Any insight? I don't tow anything and driving conditions are normal.

 

[EVO8]

I normally don't touch any tranny, rear diff fluid or spark plugs for about 60k miles, especially when I don't drive this thing hard enough. Now if your truck lives at redline all the time then maybe it would be a good idea to change it every 30k miles.

 

[BK19702]

Tranny fluid at 30K is a good idea IMO.

I changed the diff fluid early on myself, just to get the factory fluid out of the diff along with any shavings that may have accumulated as a result. Otherwise, with the synthetic gear oil in place you should be good for a substantial amount of miles depending on what you tow.

The spark plugs are kind of subjective to me. I know the manual says 90 - 100K for the spark plugs, but I have always felt iffy about leaving them that long. I had the same interval specified on my Chevy for spark plugs, and I ended up changing them at 60K just to be on the safe side. Bottom line, go by what the service manual dictates NOT what the dealer service schedule says (they'll have you in there every 10,000 miles for something if you listen to them).

 

[DeadRiver]

i'm a big fan of inspecting things for myself. i don't trust the dealerships or their mechanics.

 

[BigA]

Tranny and rearend fluid should be changed every 30K, supposidly our plugs are good for 100k, but I'll probally replace mine well before that.

 

[cneary812]

platinum plugs will last 100k easily as long as everything is running properly. They are not like the old copper ones from the past. Heck we are not that far off from them sealing the entire engine up to be serviced every 100k miles.