I need some help with an LLY question

[socaltoolguy]

Can anybody give me some advice regarding the LLY diesel. When we were full timing we had a 2001 Duramax and had no problems with it but now I'm looking at a 2005 LLY with 189k on it. What should I know about it? What questions should I ask the seller? I really want to stick with GM products and this one is in our price range. Any help you folks can give me would be greatly appreciated. Take it easy on me. I'm old. Thanks for any help.

Ray

[rapidoxidationman]

When were the head gaskets replaced? Did they use bolts or studs to clamp things back together?
Has the transmission fluid been regularly drained and refilled with a fresh screw on filter can?
Did the engine coolant get changed at 150K?
Is the truck bed whole or has there been a 5th wheel mount bolted on? (speaks to the engine's working life)
Has the seller been religiously using a fuel additive on every tank of fuel? ULSD diesel is not very slippery...

I have well over 230K miles on mine and replaced the gaskets at about 160K. Used ARP studs. Pulls like a freight train.

[socaltoolguy]

Thanks so much for your input here. Those are all questions I would have forgotten to ask. As to the bed/hitch, the owner has a 5er hitch in it and has pulled a 32 ft trailer with it so that settles that. I'll inquire as to all the maintenance you mentioned though. Is it a known problem with the head gaskets? When I sold our 2001 it had only 75k on it and I didn't have any idea that it was going to need the head gaskets replaced. I kept waiting for the injectors to go bad but they didn't. The only time it ever gave me any trouble was my fault for stretching the fuel filter change a bit too long and it quit on my just outside of Benson Az. I limped it in and got that fixed. Stupid me. Other than what you mentioned is the LLY a pretty good motor? The one I'm looking at has had the LBZ turbo mouthpiece installed on it. I'm not sure what that is but from what I have read, it's a good upgrade. Other than that, it's a stock setup. From the looks of the truck in pictures it appears pretty well taken care of.

I do appreciate your help.

Ray

[socaltoolguy]

When were the head gaskets replaced? Did they use bolts or studs to clamp things back together?
Has the transmission fluid been regularly drained and refilled with a fresh screw on filter can?
Did the engine coolant get changed at 150K?
Is the truck bed whole or has there been a 5th wheel mount bolted on? (speaks to the engine's working life)
Has the seller been religiously using a fuel additive on every tank of fuel? ULSD diesel is not very slippery...

I have well over 230K miles on mine and replaced the gaskets at about 160K. Used ARP studs. Pulls like a freight train.

Can you give me some info on the fuel additive? I had a 2001 Duramax that we full timed with and never put anything in the tank except diesel. Did I do a bad thing? I'm just asking because I want to do right with my next truck. Also, what year trucks had to have an additional tank for the needed additive? Was it 08-09???

[rapidoxidationman]

I'm not sure what year DPF became a necessary fluid for the truck to run - 2012 maybe? Someone here will tell you with more certainty.

Regarding fuel additive, I've always used Power Service in the gray bottle. Some would say it's the bottom of the barrel for fuel additives, but I've yet to have a fuel related issue with my diesel engines and I've had 6 between cars and trucks. FPPF is seemingly a preferred brand, but isn't as easy to get here. Additive will keep the fuel system slippery and clean, something today's low lubricity fuel might not do as well as it should.

[DmaxMaverick]

DPF = Diesel Particulate Filter -- 2007.5
DEF = Diesel Emissions (Exhaust, etc.) Fluid -- 2012

[rapidoxidationman]

^this