Do I need overhaul? Detroit 60 series 12.7

Drove this truck for about 8000 miles and have added 2 gallons of oil already. I'm not loosing any coolant and no big oil leaks, maybe just a drop of oil when I park I see it on ground.

Since last week lot of white smoke coming from blowby tube.

Been a company driver so I'm new to this truck of my own.

Last owner said he did engine rebuilt about 400,000 miles ago but had no paperwork.

Any advice/suggestion would help.

Thanks

 

I have no idea what kind of oil they put in. I got my oil change and complete pm service done at this big repair shop when I bought this truck but I did put in mobile delvac 1300 super when it was low.

 

Yes I'm thinking that's what happened bcuz oil level went down after around 8000 miles. I got my oil changed about 8400 miles ago.

 

Alright. I'm at the repair shop now. Let's see what this mechanic tells me here. One guy at another shop told me I need engine rebuilt when he saw all that smoke from blowby tube but I'm here at different place to get 2nd opinion.

 

I didn't go that much on mountains. I mean seen some hills but I wasn't heavy. Less then 25000 pounds of load.