wood

Is a prelubricator a good idea? Or is it just a gimick? Does it extend the life of an engine?

Commatoze

Might be worthwhile if your truck was being used for deliveries; frequents starts. But as a daily driver, I don't think you'll ever see a return in the investment.

Dieseldude4x4

This is just my opinion but you've got trucks out there with over a million miles on them and the engine has not been touched. I doubt seriously that very many have the pre-oilers. How many big rigs do you see with the pre-oilers?
Just my opinion again but I believe that money could be better spent elsewhere. I have put almost 400000 miles on three of these engines since 1989 with no pre-oilers. Drove a B 61 Mack back in the 70's with no pre-oiler, never had any problems.
If your truck sets for a month or so at a time without running, maybe it would be a good investment. If your truck runs several times a week like mine, save your money. Maybe if you live in the extreme north where it gets cold enough to freeze the, well you know what I mean, a pre-oiler would be good but in the lower half, I would not invest in it myself.

Again, just my opinion as a diesel driver for a lot of years now.
DD4X4

angleiron

Most work in two ways that may be getting missed here. A pre-oiler (at least those that I have looked at) work also as a post-oiler keeping oil flow through the engine after you shut it of so that no coking occurs to the bearings for the turbo.

The question now is, "Is a pre-oiler chepare than the exhaust gauges and running the truck for a period of time until thinmgs have colled down"? Most oilers have the option to set the pump to run for a period of time (adjustable) to keep oil flow going even after the engine has been turned off and you have walked away.

wood

My neighbor has the one that runs after you turn the engine off. Is that the same as just letting your engine run alittle after driving? Thanks for all of your input!