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6.5 daily driver started making some noise

A

Aaron1505

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Location
Northwest Indiana
Hi this is my first post here. I bought my 1998 gmc c3500 srw crew cab long bed back in October and between rebuilding the rear end and working out of town I finally got to start driving in December. When I first got the truck I thought I herd a little tick in the engine but being my first diesel I didn't know if it was just normal diesel clatter. Being in December I didn't drive with the windows down but now it's warming up I can hear what sounds like a baseball card in bicycle spokes when I drive down the road and pass something like a concrete median or a semi or something to reflect sound. It's a manual so I have pushed in the clutch while driving and the noise goes with the engine rpm. There is barely any noise at idle but it's more noticeable while driving. Oil pressure is good and the truck has 198000 miles and is bone stock. Hope I didn't ramble too long and that someone can help me with this issue as I am new to diesels. Thank you, Aaron.
 
Might check the crankshaft pulley, it has rubber molded into it, and then go bad. If you can lay under the front and move the pulley back & forth, with motor off, in the way the belt moves, the metal tabs might be hitting the housing, it makes a rattle sound and if it is bad, you could cause a crank shaft to break. other than THAT, VALVE TRAIN WOULD BE NEXT PLACE TO LOOK.
 
Thanks guys I'll check that crank pully in a min I'm getting ready to change the oil now anyways. And I was thinking of pullin the valve covers and takin a look see what's goin on in there as there is no excessive smoke at the tail pipe I didn't know if that could b a valvetrain issue? And please bear with me I'm new to diesels I only picked this thing up because the price was rite 600 bucks for a gmc yea I'm gonna buy it every time
 
Removing the valve covers isn't going to be as easy as you think, the injector lines & intake will need to be removed, then after all is put back, you will need to bleed the fuel system, we can give you step by steep info on how to do that also. It will not just crank back up when you open up the fuel system..
 
Ok I changed the oil and the previous owners took zero care of this thing this oil has about 1500 miles and it's some of the worst oil that I've ever seen except for the oil that came out on the first change. But anyways I grabbed on the crank pully and there was a little flex but it didn't spin and the rubber looks ok to me from what I could see, but I could b wrong. Looks like the valve covers are coming off next. So what do I have to do to get them off? Do I have to remove the turbo for the pass side?
 
you can leave it on, my thought would be injector. get a stethoscope and rev er up to see if one is making a noise.
 
VALVE TRAIN WOULD BE NEXT PLACE TO LOOK.
Click to expand...




Maybe check drivetrain, like suggested.......U-Joint(s)?....but they usually "squeak" more than "tick." <---- WAG (Wild A$$ Guess)

But way easier than than Valve Covers.....JMO
 
It's not drivetrain because it changes with rpm Rollin at the same speed. Unless there's something that I don't know about. The truck has 198000 on it and I know the previous owner bought it with 75000 and has replaced nothing the truck still has stock injectors and glow plugs. How long do injectors normally last? And I know that the previous owner had been running off road diesel for a while before I bought it if that could make any difference? And I know the glows can't b in too good a shape because it won't start under 25 degrees without being plugged in.
 
I changed my oem ones at about 160k and they were functioning fine. most say to replace at 100k. I think fuel quality and how hard you drive it have a bearing on it too.
 
offroad is good fuel. time for some maintenance.
remove upper intake to remove IP fuel inlet. clean screen.
remove FFM to clean. last ditch screen removal/cleaning. spray carb cleaner in bottom of FFM to remove built up gung/trash. let dry real good. add fuel pressure gauge to monitor filter/LP condition. remove injectors, get a set of rebuilds or new from a reputable vendor. change return lines for insurance. change damper/balancer for insurance.
14 years and 200,000 miles will weaken, fatigue and wear out engine components.
 
Welcome a new member to the "Hand shaker" club.
These Manual trans trucks have a dual mass flywheel that separates. See if the clutch was ever messed with. Your description sounds like a ring gear hitting something.

Next remove the fan belt and see if the noise is gone. If so you can look at the PS pump or vac pump.

Next check the turbo. Little clearance for oil is normal, but, blades scraping the housing is not.

You want to pinpoint the noise location.

Last welcome! Here you will learn things about the 6.5. Like the last owner could have just changed the oil and it will drain out coal black. Unless you put in gapless rings this is from the blowby soot entering the oil. The 6.2/6.5 is a dirty engine in regards to oil and has very little in the crankcase vs. the 12 quarts in a newer diesel V8. At least the oil level is easy to see on the dipstick.
 
I'd see if the noise is there when parked, engine running. Use mechanics stethoscope and poke around carefully and you will be very surprised at what you will hear. I had an alternator whine with a card in spoke sound on a 1993....WELCOME!!!!
 
Thanks for all the rplies! I've been outa town workin at power plants I'm a boilermaker and I travel around a bunch so I haven't been able to wrench on it. I've just got back home now and I'll let y'all know who guessed the culprit. But I'm leaning towards bmxdkj being rite, but it also could b something clutch related because the tob needs to b replaced and I know that someone has done some clutch work on her. So we will see very soon just gotta work on it while the new baby is sleeping.
 
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