I'm going to hit 25,000 miles today or tomorrow.

What should I look into maintenance wise, for my DD. I change my oil every 3,000 miles with Motorcraft full synthetic and only use Chevron 91 with my Brenspeed tune.

I've read about people changing fuel filters and getting the injectors cleaned. I also know that I should investigate changing out the two piece spark plugs.

2 cents anyone?

 

Changing Full Synthetic oil at 3k is a bit of a waste. But, I would change the fuel filter, oil & flter, tranny fluid and rear end lube.

 

Agree. Oil changes and filter done here at 5K miles. Tranny and third member fuilds are both very long life, so you could refer to your owners manual there. As far as keeping fuel system, injectors and throttle body clean. We run a can of Seafoam through the GT/CS's gas tank while travelling on those long road trips. And then just let it do it's magic cleaning thing. This basic maintance system has been working pretty well in our shop for over twenty years now. CalStang

 

Why not consult the owners manual for suggested maintenance at say 25k or 30k miles?

 

One thing people are doing that the owners manual doesn't mention (something about a TSB), is to carefully remove, apply anti-seize on the threads then reinstall the sparkplugs to keep them from seizing in their sockets.

Fuel filter is hit or miss. I changed mine out at 26k, looked fine. Others have changed theirs at 30k and the fuel they poured out was almost black.

Definitely second the seafoam application. And maybe clean your air filter? And if you don't have one, consider a good PCV system catch-can filter.