Transmission fluid change

[bellalyssa]

Since my car has hit 100,000 miles I have decided that I want to change all of the fluids in the car. I don't know when the last time this was done and I'd rather be safe than sorry.

With that said, what kind of transmission fluid should I use? I have searched around and I can't really find anything that says what kind should be used for my car. I've also read that you shouldn't change the fluid on high mileage cars because of the metal shavings, something about the transmission needing them so it doesn't slip.

Anyone have any experience/advice on this one?

BTW, my car needed spark plugs BADLY. One thing I noticed taking them out is that my car is running lean. I've been told that the 3's do that naturally, but I am not so sure. Input on this would also be appreciate.

Thank you!

[tbot]

bullshit...my old 3 ran so rich when i was at the dyno lol. All new mazdas run rich. post pics of ur spark plugs

[bellalyssa]

They are in the trash. When I pulled them they had a white coating on the end of the plug. My friend says that that's a sign they are running lean. There was only one that had it though, the others were "normal" apparently.

[tbot]

hmmm...only one plug that way isn't good lol. May be time for some injector cleaning is what it sounds like to me, or could be that one wasn't gapped properly and running hot.

[bellalyssa]

Injector cleaning... sounds... difficult.

[tbot]

I think u can just run some stuff thru ur fuel system lolz...

[chickenwafer]

What kind of transmission do you have (manual or auto)? For manual transmissions I always recommend Redline MT90...can't go wrong with the stuff. Provides excellent protection, I ran it in my RX-8. Or if you are "harder" on the trans you can do Redline Heavyweight Shock Proof, it's super thick and protects even better.

This is a picture of a plug in an engine running too lean:



Here is a general spark plug reference:

[bellalyssa]

It definitely looked like the top one.

My shop recommended BG 44k for the injector cleaning. It's a fluid you put into your gas tank to run through. He also said that if I wanted I could take the injectors out and send them out to be cleaned. I'll take the fluid lol.

Redline seems to be the preferred fluid for use. I have a manual transmission btw. Now the question is whether to do a flush or just drain the fluid once and fill it again.

[tbot]

Might as well do it right the first time...but its still weird that only ONE of the plugs looked like that first pic from chicken...but like i said, all newer mazda piston motors run rich (chicken do the rotary's run the same way too?)

[chickenwafer]

Dude rotarys even richer LOL...RX-8's run into the low 9:1 AFR stock. The Mazdaspeed cars run even richer tho...into the high 8's!

Rotaries always generally run richer than their piston counterparts...just the nature of the beast.

If only one spark plug looked lean, then you have a problem with one cylinder, so your WHOLE engine isn't running lean, meaning there IS a problem. Probably a clogged injector on that cylinder.

Just beware of fluids you pour in you gas tank to clean your injectors. Most are snake oil (i.e. Don't do anything) and some that actually DO work can cause harm to your fuel system. They can loosen deposits in your fuel tank like rust, sediment, and general dirt, cause sediments trapped in your fuel filter to be removed and flow through your system, and potentially damage injectors.

The BEST way to solve the problem would be to pull each injector, label them, send them into a company like RC Engineering or KG Parts, and have them cleaned, flow tested, and flow matched. This would be the best solution without causing harm to your fuel system, and the service is only about $25 per injector, but removing them can be a pain sometimes.

I would also recommend getting your fuel filter changed if you haven't done so already.

[Number2]

That is a good image of the differences in sparkplugs. Reminds me of my brother's tiburon which was running nitrous. spark plugs looked like crap and one blew up just like in that picture. Haha

[bellalyssa]

If I had another car to drive I would send them in, but I don't. SCR suggested BG 44k and said it was the only thing that actually did something to clean the injectors. I'll ask them about the sediment issue when I get the chance.

Is the fuel filter something I can do myself?

[tsx_guy]

My honda tech recommends BG 44k once a year for the fuel injectors. It's a little pricey 25 bucks or something. Keep in mind the guy doesn't sell the stuff so it's not like hes making a profit giving me the advice. I just ran some in my car a month ago.

no clue about the fuel filter replacement.

[roninspeed3]

I have run plenty of BG in my cars over the years and Redline too. I would recommend either or both but most of this club is a heck of a lot smarter about these Mazda's than I am. On my MS3 it's Castrol GTX and still on stock fluids, and of course the advice is not to run any additives. I'm not sure if I read that in the manual or got that here. However back in the 90's when I had GTO's, a Firebird 400 and an AC Cobra (not all at one time) I would use Red Line and BG products routinely.

[chickenwafer]

I'm not positive of the location of the fuel filter on the Mazda3. If it's anything like most 2004+ Mazda's it may actually be integrated into the fuel pump sump which means you have to replace the whole pump assembly.

At least that's how it was on the RX-8...you couldn't actually change the filter, you have the change the whole pump assembly. The good news is, for the RX-8, the pump assembly was only $155 bucks. It isn't a bad idea to replace your fuel pump at 100k miles, either, I'm pretty sure that's the recommended service interval for it anyways.

You could call a Mazda dealer and ask about the filter, or check http://www.onlinemazdaparts.com for the filter. If you can't find a fuel filter then it's integrated into your pump. EDIT: Just check the linked website and it appears you don't have a separate fuel filter, the filter is integrated into the pump assembly. Mazda3 owners can correct me if I'm wrong. The whole new pump is $340.61 plus shipping. Going to a dealer it will be over $500+. Plus you will probably need a special tool to remove it since the pump is in all likelihood held in by a giant plastic grooved ring that requires a special tool to remove, or you can attempt the hammer and pry bar method which 99% of the time breaks the plastic ring. Good news is the ring is only $25 usually for a new one...

At 100k miles you should also check your timing belt, adjust valves, and flush ALL fluids and replace all filters (motor oil, oil filter, power steering fluid, trans fluid, limited slip fluid [if applicable], coolant), check your radiator cap, and hoses, etc. 100k miles is a lot of miles so you want to make sure everything is good.