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Discussion Starter · #1 ·
Well bought this truck recently, checked and found a bunch of sludge in the oil. Heard the lifter tapping this morning. Gonna do oil change and any other suggestions?? I've only drove it for 2 days and now gonna park it til this work is done.
Any suggestions would help 馃槈
 

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How many miles?

There are cleaning agents that will remove the sludge, and a number of home made efforts.
@j cat has one a lot of people have used.
 

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Discussion Starter · #3 ·
How many miles?

There are cleaning agents that will remove the sludge, and a number of home made efforts.
@j cat has one a lot of people have used.
It's got 176,000 ... Running good after new cap/button, plugs and wires, fuel filter, brake caliper and pads. Now on to the oil issue.... It's been sitting for quite some time.
 

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Discussion Starter · #5 ·
J cat will be on tonight, he has a solution that uses Marvel Mystery Oil
I'm definitely waiting for his reply, I've scrolled through his stuff and can't find his "instructions" 馃し馃徎鈥嶁檧锔
I just don't want to have to get rid of it. Some say sell it, small motor/big truck... But I don't want to. It runs well!
 

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4.3's aren't really known to sludge up, this truck was abused.

You can run motor flush products like motor medic, also you can run marvel mystery oil as well and over time it will start clearing out the sludge.

Another product that many seem to have good luck with is Rislone Engine Treatment this product I have seen multiple videos silence noisy lifters and it also helps clean out sludge over time. This is probably among the more safer products along with Marvel Mystery Oil because they can be left in the oil for the oil change interval.

Either way don't have too high of hopes with a fix in a bottle they don't always work. There is another product which works amazingly but you need to find a shop that can get it for you because they do not sell it to people it is shop only

BG Dynamic Engine Cleaner & Rinse Oil | BG Products, Inc.

If it were me personally I would try Rislone and go with a full synthetic oil to help clean it out.

But depending on how bad off it is the engine may be too far gone.

And for people who say small motor big truck, the 4.3 has plenty of power I had a 1994 Silverado with a 4.3 TBI which is a even less powerful version and that truck was beat up and abused with over 250,000 original miles and it was still running when it was sold. That truck was used for scrapping and hauling heavy loads and moving homes.
 

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The reason you have sludge is because the engine oil is conventional engine oil, fossil oil. This type of oil will turn to sludge when the engine is used in a lot of short trips, the engine doesn't spend a lot of time at full temperature. The cold engine attracts moisture and it mixes with the oil. It will evap if engine runs at operating temps for awhile, if it doesn't evap it mixes with the oil and turns to sludge

The best oil to use is full synthetic. Synthetic does not form sludge. Yes, it's more expensive; but you can run it longer, just use a good long life filter.

When you start to remove the sludge, take it slow, you want it to melt. If it comes off in lumps it can plug an oil passage.
 

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Discussion Starter · #9 ·
Hey! Thanks for the info. I do know the man who owned it, older gentleman and he bought it brand new. Could it have sludged up because it sat for quite some time? I bought oil, filter and engine treatment (motor medic) and fixing to do an oil change tonight. The oil hand fluctuates between 20 and 60.... Normal? Or does it sound like the pump is going out? The truck runs great, I truly wanna keep it.
4.3's aren't really known to sludge up, this truck was abused.

You can run motor flush products like motor medic, also you can run marvel mystery oil as well and over time it will start clearing out the sludge.

Another product that many seem to have good luck with is Rislone Engine Treatment this product I have seen multiple videos silence noisy lifters and it also helps clean out sludge over time. This is probably among the more safer products along with Marvel Mystery Oil because they can be left in the oil for the oil change interval.

Either way don't have too high of hopes with a fix in a bottle they don't always work. There is another product which works amazingly but you need to find a shop that can get it for you because they do not sell it to people it is shop only

BG Dynamic Engine Cleaner & Rinse Oil | BG Products, Inc.

If it were me personally I would try Rislone and go with a full synthetic oil to help clean it out.

But depending on how bad off it is the engine may be too far gone.

And for people who say small motor big truck, the 4.3 has plenty of power I had a 1994 Silverado with a 4.3 TBI which is a even less powerful version and that truck was beat up and abused with over 250,000 original miles and it was still running when it was sold. That truck was used for scrapping and hauling heavy loads and moving homes.
 

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Hey! Thanks for the info. I do know the man who owned it, older gentleman and he bought it brand new. Could it have sludged up because it sat for quite some time? I bought oil, filter and engine treatment (motor medic) and fixing to do an oil change tonight. The oil hand fluctuates between 20 and 60.... Normal? Or does it sound like the pump is going out? The truck runs great, I truly wanna keep it.
Be certain to follow the directions on any motor flush products you use such as the motor medic. Sitting can cause moisture to build up and it also turns oil acidic which can cause harm as well, it can sludge up from sitting for a very long.

I own a 2003 S10 4.3 and it idles around 40psi however it is not uncommon for 4.3's to idle around 20psi when warm, your sludge could also be causing some starvation issues causing it to fluctuate but another common issue is the oil sender/sensor going bad causing the reading to go crazy.
 

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Discussion Starter · #11 ·
The reason you have sludge is because the engine oil is conventional engine oil, fossil oil. This type of oil will turn to sludge when the engine is used in a lot of short trips, the engine doesn't spend a lot of time at full temperature. The cold engine attracts moisture and it mixes with the oil. It will evap if engine runs at operating temps for awhile, if it doesn't evap it mixes with the oil and turns to sludge

The best oil to use is full synthetic. Synthetic does not form sludge. Yes, it's more expensive; but you can run it longer, just use a good long life filter.

When you start to remove the sludge, take it slow, you want it to melt. If it comes off in lumps it can plug an oil passage.
Can you explain "take it slow"
Thanks
 

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Can you explain
Thanks
Here is a pretty good explanation:

At this point I wouldn't jump into replacing the pump.
I think you said the pressure needle was bouncing a bit, the best approach is to go to a parts store and have them lend you a pressure gauge, compare the 2 gauges and watch for the bounce on the loaner.
If no bounce, it could be the sending unit, or the dash gauge.

Edit:
Sorry, my fingers typed "would jump" should be "wouldn't jump", I fixed it.
 

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Discussion Starter · #15 ·
If it's tapping pretty good, what's y'all's opinion? Just did the mobile medic and draining it now. Have full synthetic oil to put in it when done. I've not heard from jcat on his MMO fix....
 

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Jenna, post #2 is one of his:

 

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If it's tapping pretty good, what's y'all's opinion? Just did the mobile medic and draining it now. Have full synthetic oil to put in it when done. I've not heard from jcat on his MMO fix....
Can you provide a video or audio, I want to make sure it is not being mistaken as an exhaust manifold leak.
 

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Discussion Starter · #18 ·
It's not the exhaust. But .... 馃う馃徎鈥嶁檧锔 He took off the valve covers due to it still chattering after the new oil, and there was no oil coming out of the push rods. Oil is just now coming out...
 
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