At what point is everyone doing a coolant flush? Is it worth my time doing the entire process myself or should I just buy the antifreeze and have the shop put it on the machine that completely flushes it out until it is sparkly clean? Does anyone know how much antifreeze to take to the shop, if so?

Same goes for differentials...at how many miles is everyone changing that?

 

Does your owners manual state recommended service intervals for such things? Sounds like you better have someone else do it for you.

 

Coolant flush is absolutely necessary every 2 years or 30,000 miles. The coolant simply doesn't remain effective unless it is designed for extended drain intervals.

If you go to a shop, I'm not sure they'd allow you to use your own antifreeze as they make money selling it. Dealers charge around $60.00-$80.00 for the flush which I think is quite resonable for the amount of time invovled when changing it yourself.

I'd suggest that if you pay someone to flush it then you should add a bottle of coolant flush before driving in so it has some time to break up the scale in the system and then get flushed out.

If you do it yourself, it takes a few hours as well as 3 gallons of antifreeze and 3 gallons of distilled water. The Chiltons and Haynes manuals both have fair descriptions of the procedure.

Differentail fluid may depend on vehicle year. My '97 manual states every 30,000 miles but I believe that Ford now uses a synthetic and says you never have to change it.

I believe it should be changed every 30,000 miles regardless of Ford's opinion. There are a lot of people having differential failure and Ford can't explain why. When I changed my differential fluid, there was definately water contamination and my differential has never been submerged. It should be worthwhile to remove the cover and change the fluid every 30,000 miles.

 

Thanks for the info! My shop will allow me to bring my own anything, so I will definately have them do it so I don't waste a day off hassling with it. The manuals do give recommended intervals, but I don't trust it. They say spark plugs last 70k+, but I had them changed at 48K, and they definately needed it. The garage even tried dissuading me. They also say shocks last longer than they should. I replaced those myself at around the same time, and the rear ones could be compressed all the way with light force.

I'm definately on board with preventitive maintenance!

 

Thought I'd point out that in the service manual (on my '98 anyways) that it calls for the first engine coolant flush at 50,000 miles then after that it calls for it to be done every 30,000 miles. The transmission fluid on the other hand it supposed to be done for the first time at 30,000 miles and done every 30k.