1mark

Is it save to use engine flush before an oil change?

spinellib

Yes, but I would use a quality product and follow the directions. I don't think the "flush" products do harm, but not sure they do any good.
For instance, old timers like to use Marvel Mystery Oil in the crankcase before an oil change. Modern engines don't need or like products such as MMO or Seafoam.

Fuel Treatment is good. You might be better off just using some Redline Complete Fuel System Cleaner or Gumout Multi System Tune Up. Both products contain PEA, a powerful chemical solvent for breaking down and dissolving carbon. If you'd like, you can even dump some of the Gumout into the oil and run the car for a bit before changing the oil.
So if you do want to "flush" your engine, I'd recommend the Gumout Multi System or Gumout All In One Complete Fuel System Cleaner.

Do both if you want. Dump a bottle in the fuel tank, and another bottle in the oil.

cdnewton

What makes you think you need an engine flush? Has the vehicle been neglected? Do you change your oil regularly? Do you use the proper API certified oil? Lots of questions.

1mark

Oil change every 3k
New filter
Oil looks clean not dark on the dipstick.

Just on some cold start ups I hear a valve rattle for a moment or two.

tomr51

rattle is "normal". if the car has been well maintained, i would not do a flush. sometimes they can do more harm than good

1mark

Thanks, I was looking for the normal information

Felix

If you want to add chemicals to clean your rings/lifters, I'd drain a few qtrs & add 2-4 qtrs of atf & drive it easy for a day or two.
I'd use a good synthetic oil & filter.....

iMSQ

No issues with the engine? Just do regular oil+filter changes. No chemicals.