Just bought a 1995 GMC C1500

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84c10Tony

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Rough idle

Have you had a chance to run a can of Berryman's B-12 through the gas tank? And spray the tb with the B-12 spray can, might help before the tune up to have another "clue".
One could look at plugs and cylinders for the before and after...might be interesting, Especially with your photos.
Good work man.
 

HotRodPC

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Have you had a chance to run a can of Berryman's B-12 through the gas tank? And spray the tb with the B-12 spray can, might help before the tune up to have another "clue".
One could look at plugs and cylinders for the before and after...might be interesting, Especially with your photos.
Good work man.

If you ran the Berrymans in the tank, don't run the SeaFoam. And damn sure don't put both in the tank at the same time. I'll also mention, don't think more is better in the gas. You get to much in the gas, it'll possibly be bad on the new Cat Converter. I'm certain 1/2 can of SeaFoam for 25 gallons won't hurt the converter.
 

84c10Tony

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HR and I where posting at the same time, just took me a lot longer to type lol.
Yeah, only run Sea foam or B-12, never both, I personally have only used B-12 about twice a year for 30 plus years, the original cat went out many years ago after some other problems, been ok since.
Always follow the directions for the amount, I was not a chemist, nor do I play a doctor on tv.

Excuse my inclusion HR, I would not have mentioned B-12 if I had seen your mention of anything else no matter the product, last thing I had seen was his tune post. Pardon' Oui'.
 
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HotRodPC

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HR and I where posting at the same time, just took me a lot longer to type lol.
Yeah, only run Sea foam or B-12, never both, I personally have only used B-12 about twice a year for 30 plus years, the original cat went out many years ago after some other problems, been ok since.
Always follow the directions for the amount, I was not a chemist, nor do I play a doctor on tv.

Excuse my inclusion HR, I would not have mentioned B-12 if I had seen your mention of anything else no matter the product, last thing I had seen was his tune post. Pardon' Oui'.

No biggie, I was thinking you mentioned the Berrymans early on this thread when I seen your post and just wanted to make sure he didn't do both.
 

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Ok guys, here's a new one for ya. I have a coolant leak between the back of the engine and the transmission somewhere. When I bought the truck and towed it home, there was a box with an old water pump in the back seat. PO said he had it changed out before the engine seized. I'm hoping the ass clown mechanic who told him that, and put the water pump on, put it on without gaskets, and somehow the coolant is running towards the rear of the block.
 

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If it's between the engine and the transmission, it's a freeze plug in the back of the block and the transmission is going to need to come out. Are you sure it's not somewhere else back there, like maybe the firewall? Maybe a heater hose up against the firewall is leaking? Heater core possibly?
 

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If it's between the engine and the transmission, it's a freeze plug in the back of the block and the transmission is going to need to come out. Are you sure it's not somewhere else back there, like maybe the firewall? Maybe a heater hose up against the firewall is leaking? Heater core possibly?

It started getting late, so I'm gonna investigate more tomorrow. Can I see if there is a leak on the freeze plugs by taking of the flex plate cover and looking in there with a light?
 

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You might have enough access up there to see it. Or you have the fancy handy dandy rootin' tootin' cam that you can send up there to check it out for sure.
 

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You might have enough access up there to see it. Or you have the fancy handy dandy rootin' tootin' cam that you can send up there to check it out for sure.

WTF! Thanks for reminding me, I keep forgetting about that damn camera. That's exactly what I'm gonna do tomorrow.
 

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No worries, we're here to take care of your senile ass. That truck will be in good shape in no time. :laughing1: And I wouldn't have touched 1 wrench.
 

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No worries, we're here to take care of your senile ass. That truck will be in good shape in no time. :laughing1: And I wouldn't have touched 1 wrench.

:cheers:
 

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Yesterday while I was out driving it around, I also noticed that, when at a stop light, with your foot on the brake, it idles just fine. When you slightly let off the brake and inch it forward, it wants to lunge/tug a bit. Transmission?
 

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Yesterday while I was out driving it around, I also noticed that, when at a stop light, with your foot on the brake, it idles just fine. When you slightly let off the brake and inch it forward, it wants to lunge/tug a bit. Transmission?

I'd wait to see what else goes on with the transmission before I panic about that. It might just be a tight converter. I'd be thinking something in the torque converter more than anything with that kind of issue.
 

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So, the truck is running awsome, no more noise fron the cat. Although I still have a noise comming from somewhere, like a subtle scraping, everytime I put it in gear, also the subtle Jerking at stop lights when I let off the brake and inch it forward. I've already put 347 miles on the truck since I got it running, engine is running smoothly, transmission is shifting flawlessly. I took off the front wheels and found something interesting in side the wheel cap. Two little peg/pins, just laying in there, and I have no ******* clue what they are or what they are for.
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Honky Kong jr

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So, the truck is running awsome, no more noise fron the cat. Although I still have a noise comming from somewhere, like a subtle scraping, everytime I put it in gear, also the subtle Jerking at stop lights when I let off the brake and inch it forward. I've already put 347 miles on the truck since I got it running, engine is running smoothly, transmission is shifting flawlessly. I took off the front wheels and found something interesting in side the wheel cap. Two little peg/pins, just laying in there, and I have no ******* clue what they are or what they are for.
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Might wanna check them wheel bearings.......unless some one was being a wise ass and put them in there to freak someone out. Kinda look like bearing rollers.
 

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