I am in a pickle. I scheduled a flush with a dealer and then I had the bright idea of changing the thermostat. It has 135k miles on original thermo and I want to change it myself because the dealer is going to charge 125.00 just for the thermostat change and then another 140 for the flush. I don't mind the flush, but that is crazy for a thermo change. Is it possible (somewhat) easy to change the thermo without draining all the antifreeze? THen I can do this and still have it flushed?

It's a 99 5.4 with 135k miles if that makes any difference.

JayHops

 

You need to drain the coolant at least past the t-stat housing; does the coolant have 135k on it also?

Steve

 

Yes, the coolant has that many miles, never had any heater or cooling issues, and still don't. I just know it was time to replace the coolant a long time ago and never wanted to pay to have it done, but now with the miles and everything I will concede to the dealer. This site has helped me do all the other PM stuff. I know it's time for coolant, and I will drain it low enough to do the thermo today and take it to be flushed tomorrow.

 

I'd be finding a different mechanic if I was you, if they're charging you $125 to change the thermostat since they're doing a flush anyway.

 

I agree, especially considering the t-stat can be changed in under 10 minutes when the truck is in to get the flush done.

 

You can probably tell by the looks of the coolant drained out of the radiator whether a flush is necessary.

Does that $140 dealer flush include enough antifreeze to give you a 50/50 mix? Do they use distilled water?

If not, this is what I'd do (assuming a 16-18 qt. coolant capacity): Buy 3 gallons of Ford antifreeze and 3 gallons of distilled water; drain as much of the radiator and coolant recovery bottle as possible, then change the t-stat and gasket/o-ring; mix the water and antifreeze so you have 6 bottles of 50/50 coolant; fill the radiator and bottle, then run engine for 5 minutes; continue draining/refilling/running until your mix is gone. If you don't have a way of catching/disposing of the used coolant, then let the dealer flush it.

I've used this method on all my rides for many moons, but no later than 3 years/36K miles.

Steve

 

I agree the dealer was ridiculous and I tried to negotiate with them, thinking that with the economy, etc.. they would take any work as opposed to no work. This is an actual dealership to, not a general mechanic.

Thanks to you folks, I did replace the thermo without any issues. I was actually kinda low on coolant. The thing I did incorrectly or maybe it can't be helped is when I took the cover/housing off, the thermostat was pumping coolant thru the air hole on the thermo - so I had a little fountain - maybe I didn't let it cool down enough, or not disconnecting the battery, or maybe just a general gravity/vacuum dynamic sort of mystery - smile. But it's changed. I actually found a piece of "rust" like material that is actually hard not just residue rust inside the old thermo. I will see if I know how to post a pic.

I filled with 50/50 mix as stated above by someone (thank you) and will let the dealer flush tomorrow morning. I would normally try myself (thanks to this site) but disposing of it is a pain - but I have tonight to think about it. The more I think about buying a few gallons versus the 140 I might get the courage to do it myself. I assume the dealer uses some sort of pressure to help get the crap out of the channels and stuff (without damaging the system). If not, then I could do what you folks suggested and just collect the coolant in a big bucket to recycle.

What coolant would you folks suggest? I have a local napa shop or walmart and even the dealer if needed to buy coolant. Do you think just drain/refill will be enough to get all the gunk out. Admittedly I shouldn't have let this go this long and it's embarrassing. But I am doing it now at least and I love my expy - I have maintained it quite a bit and it's done me well.

I tried to insert the image from google web albums and copied it correctly but it didn't seem to post. This is what I had, but I removed the img piece so you could see it.

http://picasaweb.google.com/lh/photo...eat=directlink

http://picasaweb.google.com/lh/photo...eat=directlink

 

If you have junk in that old coolant, a flush is probably an excellent idea IF enough antifreeze is included for a 50/50 mix and distilled water is used.

Steve

 

Just empty all the coolant from the system. If there is any "junk" coming out, thoroughly flush with a garden hose. In the top and out the bottom. Fill completely with plain water and run the engine. This will cycle the leftover antifreeze out of the lines. Empty the water and refill with your 50 50 mix. Voila. Saved yourself 100 bucks.

 

Holy Cow - what a process! It's done though and everything seems to be working fine. No gurgling with the heater or anything and MAN was it messy as a process and it really really needed to be done. I drive the rig pretty hard and this is something I won't neglect again. Thanks guys for all the feedback, advice and time.

My next project will be the air conditioner - it seems to work OK, but not great so will be doing some FTE research. Thanks again!

 

Man, I wish I had caught this thread sooner. When I'm changing T-stats and flushing as a preventative measure, I like to bite the bullet and change all hoses and clamps as well.