Does anyone use additives in their older diesels? If so, why products do you recommend. I'm wondering if a regular additive in a 1985 300SD would be smart and help the life of the car.

Thanks.

 

I filled my fuel filter w/ diesel additive sold at walmart.
Car ran/runs the same.

 

Marvel Mystery oil is good. Also LUCAS additives are good. these are added to the fuel system. I've used both over the years in my 81 300cd.

 

marvel is good, howes is what the truck drivers in my area use,. i run marvel or howes with diesel kleen. when i got this car (81 300 cd) it ran rough until i used liqui moly diesel purge and ran a few tanks as described. now no surging and easy starts.