Should a 2003 4x4 Tacoma with 320,000 miles, get an engine flush or will it hurt the engine?

I have a 2003 4x4 Tacoma with 320,000 miles. AAA is going to replace my spark plugs & timing belt/water pump tomorrow- 04/01/25. They suggested I get an engine flush.
Some reviews say it’s good for high mileage vehicles, however other reviews say this can be bad for an engine as it gunks up what’s inside, weakens the bolts/seals, etc.
I do get high mileage synthetic oil. Your thoughts?

 

Don't do it. Leave well enough alone.

 

I’d flush it and have them clean the maf sensor, too.

 

If you need to ask, you shouldn't.

 

I flush mine with BG EPR, pretty much every oil change,,,,5000 miles,,, also do the same to my wifes Highlander,,, it cut down on my oil consumption on the Taco by about half.