Hairline crack oil pan. Fixable ?

Same as plastic, buy a new one.

Actually, fiberglass is worse than plastic. All the fibers in the area absorb the oil.

60 series?

 

Always buy new. Sure you can patch an oil pan. But the problem is in the name. Fiberglass. That crack may be repaired but the overall integrety is comprimised so the patch may hold forever. Or it may open up at the first pothole. Imo a new pan is going to be way cheaper then potentially dumping your oil on the ground, potentially a tow, or a VERY pricy road call. if your really unlucky if the pan fails entirely in a catastrophic manner it could cause engine damage too.

Only time id patch a pan is if it was to limp from the middle of nowhere to the nearest shop personally.

 

What is the cost of a new pan for your truck? Depends on where the crack is, a pic would help. It would be best to remove the pan. You need to 'stop drill' at the end of each crack. Which is to drill a hole, say using a 3/16" bit, at the end of each crack. This relieves the stress and prevents the crack from extending. Depending on how smooth the area around the crack is you may have to roughen it up a bit so the cloth and resin adhere to the surface. Clean the area with brake clean and then use fiberglass cloth with resin using several layers. Extend a few to several inches out from the crack. Then fill the holes with resin. You could do this on both the outside and inside of the pan.

 

I'm not skilled at fiberglass repair. I would be concerned with fiber mesh or bits of resin getting in the oil pickup tube or splashed in the bearing oil grooves.
My choice would be to replace with a metal oil pan. If available.

 

Buy a new one. Too much potential risk.

 

On my old 1979 KW had a BC1, had a leak on the oil pan which was a hairline crack. It was cast aluminum, I just bought an aftermarket pan and replaced it myself. Problem solved.

 

Temperature fluctuations will make your life miserable. Just replace it with a new one.