Should I use an engine flush before changing oil?

[Joe Morreale]

I wouldn't flush it. Like Mike said, you could possibly knock chunks of gunk into bad places. I am a proponent of using high detergent oils though. If there is any sludge it will dissolve into the oil, over time. Unless your car has a known issue for sludge buildup, like my Toyota, I wouldn't worry about it. Just use a quality synthetic and a good filter. If you're taking to a quicky change, you can bring the filter of your choice. You would probably have to go to a repair shop if you wanted them to use your oil though. I've been using Valvoline 15 minute change on the Toyota, with full synthetic. It's like $75 but you can find coupons.

[Agent☣Orange]

This is all foreign to me, but I thought carbon buildup issues on DI motors was an intake manifold/head port issue. Is the carbon buildup in places the oil flows?

That’s true. The issue with DI motors is the intake getting a little build up, not related to anywhere oil flows. I don’t think any fuel additive could “clean” out any intake on a DI motor but then again, I don’t think the intake is fouled in any measurable amount to cause problems.

From my experience working on Volkswagens, it was build up on the intake valves. Never heard of carbon build up inside the engine.

But unless you've owned it since new, I wouldn't trust running an engine flush. If the PO didn't maintain it properly, there could be sludge build up. And once it starts breaking up. You risk clogging the oil pick up, and starving the engine of oil.

I've seen people have success with running seafoam/trans fluid through the engine before an oil change. But then I've also seen the ones that turn into a nightmare.

I see the point and I saw that Scotty video where he talks about engine sludge getting dislodged and clogging stuff after a flush. My car specifically was a local, one-owner bought in Venice. The Carfax report showed timely oil changes at the same dealer and I did check the oil before buying the car at Gettel. I noted the oil was a little dark (not honey new as it should have been) and they gave me that free oil-change coupon. My motor has 33K miles and there is no sludge.

I wouldn't flush it. Like Mike said, you could possibly knock chunks of gunk into bad places. I am a proponent of using high detergent oils though. If there is any sludge it will dissolve into the oil, over time. Unless your car has a known issue for sludge buildup, like my Toyota, I wouldn't worry about it. Just use a quality synthetic and a good filter. If you're taking to a quicky change, you can bring the filter of your choice. You would probably have to go to a repair shop if you wanted them to use your oil though. I've been using Valvoline 15 minute change on the Toyota, with full synthetic. It's like $75 but you can find coupons.

I’ll probably not flush it and just drain and fill. I have the new GF-6 oil and a Wix premium filter so that should be good enough. I was just looking to spend money I guess. You know how auto-parts stores are like Toy R Us for grownups.

I was just kicking around the idea of Seafoam because it can be added to both fuel and oil. My riding mower is now surging a lot and won’t run stable unless at full throttle. I know it’s the low-octane Ethanol gas causing a problem in the carb but getting to it on a Briggs V-twin motor is a bit of a pain. I thought I could get some Seafoam and pour a bit in the mower’s fuel tank and the rest in my car’s oil before a change.

[minuteman048]

Buy ethanol free gas for your mower. You can get it at any Marathon station.

[pdexta]

Hmmm, my weed eater has been giving me fuel issues. Last time I just ordered a new carb, but maybe seafoam would be worth a shot. Anyone tried it in a 2 stroke?

[Agent☣Orange]

Come to think of it, my leaf blower is bad too. It?ll idle on full choke but then die if I open the throttle. I have a carb replacement kit in my Amazon cart but I might try Seafoam first.

I?ve heard for years about people running it in 2-stroke motors like boat motors but unsure about garden equipment. Ran across a few YTubes: