01Chevyman

First time posting to this forum. Bought an 01 Chevy Silverado LT Z71 with 151K on it last month after 10 years of not owning a Chevy. Had a 95 Z71, great truck, regret selling it why I bought this one.

Haven't done a whole lot to it since I bought it.

• fixed tailgate latch with metal clips
• had a local chevy dealership flush the transmission

Already bought the parts to:

• fix intermittent knock sensor code just have been clearing it for now (bought GM knock sensors and new style harness, felpro gasket)
• ball joints, CV axles, wheel bearings, and tie rods to fix the front end.

Today I was moving a trailer into the driveway (to haul away the wrecked F150 that insurance gave me the money to buy this Chevy with) and noticed a weird smell, got out of the truck and looked on the ground and coolant all over I already knew since it had that sweet smell to it that coolant has. Killed the truck immediately since aluminum heads won't take a beating like steel. It got hot but never pinged out. Looks like it hit 240 or 250 but never hit the red at 260 degrees. I also hooked up my OBDII scanner to be sure of no codes - only one code popped which was the knock sensor bank 2 pending.

I have attached a picture of the leak I saw immediately after popping the hood. Has anyone had this leak before? Looks to be common at the firewall by a quick search but I did not see anything on the other end of the heater hose going bad. Also think I did any permanent damage getting it up to around 250 degrees?

kevinkpk

If it did 250 only I'd not worry.

01Chevyman

Thank you Kevin. Hoping so. If it runs at 210 normally I figure an extra 30-40 degrees for only 5 minutes or so wouldn't kill the engine. Or at least I hope. I am glad it happened while I was in the driveway and not driving around.

I can't believe Chevy designed it that way. I am going to replace all the plastic connections on the heater hose and overflow tank to be safe considering age and mileage and the fact it got hot probably accelerated the other plastic fittings giving out.

I just ordered the attached. Will be here Saturday so worse case should have her running again by Sunday.

01Chevyman

Okay, got the heater hose replaced with the new AC Delco, put new dorman quick disconnects on the heater hose ends at the fire wall. Interestingly the hose I pulled off which I assume is stock since it still has the marker lines on it where it snaps in the holder had the quick disconnect built in. The one I bought off Amazon did not but no big deal, one hose clamp later and had it going. Everything went smooth and fast and got it done in about 30 mins. Only thing was when I popped off the old heater hose (that plastic tee with the pinhole leak broke with very little pressure applied) green anti-freeze came pouring out not the orange stuff (Dex or whatever its called) they put in Chevy's. I ended up just topping off the coolant with universal since already had some in the garage and that is what came out anyways.

Next thing is, it ran under 210 for the following couple days. I then took a trailer out to the farm which is about 40 miles away with the 1500. Trailer had no load, it stayed under 210 until the last leg of the trip it hit 240 quick and stayed there for the last 5 mins of the drive until I got the trailer off and unloaded (I kept a close eye on it, if it had broke 250 I would have shut down and let it cool down). I let the truck sit for about 20 mins while drinking a beer with the guy who lives out there. Trip back stayed under 210 whole way again.

So questions I have (sorry I am full of them) and I do appreciate any advice you guys give. I am so used to Ford's owning a Chevy and working on one (I will admit Chevy's are easier to work on) makes me 2nd guess myself.

1. Will it hurt to have green universal anti-freeze in there? - If there is any adverse affect known I don't mind flushing it out and replacing the fluid. I am thinking of replacing the water pump anyways since I have no service records on the truck.
2. Do you need to burp the coolant system on an LS engine? There is no rad cap that I see (if there is one its under plastic), only the reservoir cap and unlike my fords its pressurized so figure only way to fill system right? - trying to figure out why it hit 240 and stayed there awhile. When it got hot I checked all fluids. Anti-freeze was at proper level on res as was tranny fluid (yes checked while truck was running) and oil.
3. Do you think maybe my water pump is weak? - my 2nd guess unless I didn't properly burp the system like you have to do on older fords and I am thinking new water pump and flush coolant to be safe.

Also you can add to the list of things done to the truck. I installed some China knock off tow mirrors I bought from eBay. Wow, you see so much more with those. It was scary easy and had both on in 10 minutes. Pop the one cover and 3 bolts your done.

kevinkpk

I don't think it's the water pump, my comments in red.

01Chevyman

Kevin thank you again!!! Your the only one helping me so far. So I take it to burp the system, pull the cap on the res, run the truck awhile until it gets to temp and all bubbles come out? - unless their is a rad cap under the plastic I don't know about.

And I am guessing all this dexos oil and dex-cool antifreeze is just a way to make a few extra bucks at the parts store, dealership, and quick lube places? You guys may cringe but oil is oil from my understanding, main difference would be additives. I bought a bunch of 5w-20 motorcraft (ford) full synthetic oil when it was on sale awhile back (paid $20 for 5 quarts so I bought 5x 5 quarts for $100 shipped no tax) but have yet to use it since I take my newer truck still under ford warranty to the dealership for oil changes so I won't have any warranty issues. I figure I was going to use it in this truck since weight is to spec I doubt it matters that ford makes the oil vs any other manufacturer. I saw on other forum postings many use synthetic oil vs dexos oil. I didn't have AC Delco filters yet so I just had a conventional oil change at a quick lube place day after I bought the truck but they did try and sell me dexos first before I shot it down. Got the filters in the mail the other day but after some reading it seems many don't like the PF61Es. I didn't see any PF61s for sale only the E version.

01Chevyman

So should I just pull that res cap off and let it get to temp to get the air out of the system like a ford? - well on a ford I would pull the rad cap but looking at radiators online it does not appear there is a radiator cap for my Chevy. Give and take I guess. Ford OEM comes with plastic reservoirs on the side of the radiator which are prone to failure (I overheated my dad's truck that way, still need to yank that engine, replaced head gaskets for them to pop again only 20K later probably need to re-deck the block this time around). Chevy decided to go with plastic quick disconnects, a plastic tee in a heater hose, and a pressurized plastic external reservoir. Sure as heck was easier to swap out the heater hose and quick disconnects, and even possibly the plastic reservoir, then it is for me to pull and install a whole new radiator on a ford.

On that note I am going to replace that heater hose and quick disconnects every 3-4 years if this Chevy makes it that long. I am hard on my trucks.

01Chevyman

Update to this post.

It never did pop up that high again, I did pull res cap and got it up to heat to burp it like I do on my fords. I then had the local chevy dealership flush the system and fill it back with dexcool to be safe.

Thanks for the help.