Fluid Changes

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TX87R10

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On a slightly serious note I have been trying out stp 0w20 high mileage with the seal additive to see if it would help with leaking valve seals and it seemed to have no effect so I switched back. Flame me...
 

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On a slightly serious note I have been trying out stp 0w20 high mileage with the seal additive to see if it would help with leaking valve seals and it seemed to have no effect so I switched back. Flame me...
That strikes me as water ...

But, I would like to try the Valvoline Restore in 5W30.
 

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bucket

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I think he is asking a serious question. There is so many different oils.
In all of my flat tappet, gas engines, I run Valvoline VR1 20w-50. Good for everything about a square. Plenty of zinc for the cam, heavy enough for the high rpms and heavy loads. Here we go...

Lol, I definitely wasn't asking a serious question, but there were a few folks such as yourself that gave good advice just in case. So @idahovette fear not, there's posts here to steer folks in the right direction.

Sorry to those that didn't know the inside joke that I was poking at. And while this thread did get some funny responses, I don't think I got a mention in either thread I was shooting for :rofl:
 

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What is the inside joke? Share with the rest of us. It looks like a pretty average post for this forum.
 

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I'm running the same 5w30 conventional (whatever is on sale and isn't a No Name Brand) in my wife's 05 Yukon until I find all the oil leaks, at which point I'll run something fancy.

I bought the truck and didn't know the service history, so like every other vehicle I purchase, I changed all the fluids - some by choice and others by failed parts (coolant leak that needed a rad change and speedo cable drive seal that leaked most of the fluid onto my shop floor).
 

bucket

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What is the inside joke? Share with the rest of us. It looks like a pretty average post for this forum.

I posted a mechanical question, but gave ZERO info about the application, to poke at one member (all in fun) and also misspelled "axle" to poke at another member. Again all in fun.

But my joke thread still turned out to produce useful info from members here, which is a good example of why this place is so great :)
 

bucket

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I recall sitting in the back of a CH 53 packed in like sardines flying nap of the earth across Afghanistan. The other Marines were probably thinking about their families back home and if they would see them again. Me? All I can think about is the constant drip drip drip of hydraulic fluid leaking from the pipe overhead and running down the side of my neck. I finally got the cargo masters attention, it was dark and we were lights out, and told him the leak might be a problem. His response: Nah, were good, let me know when it stops leaking then we have a problem. Wonderful. Now I'm curious how flammable hydraulic fluid is. :hmm:

Apparently the vapor from a high pressure leak can be flammable, but other than that, it's hard to make it burn. Putting hydraulic oil on a bonfire is almost like putting water on it.
 

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That strikes me as water ...

But, I would like to try the Valvoline Restore in 5W30.

That's what I started running a couple changes ago. I will say the oil comes out DIRTY at 3k miles.....it must be doing something
 

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That's what I started running a couple changes ago. I will say the oil comes out DIRTY at 3k miles.....it must be doing something
Notice any difference in oil consumption, power, or fuel economy?
 

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Notice any difference in oil consumption, power, or fuel economy?
Not in consumption, because I lose all my oil through the valve stem seals :).

I switched bc the oil pressure at hot idle was a little low compared to a few years ago. Used to idle around 28-30psi and was idling at 20-22psi this summer. After a couple oil change intervals, it does seem to be more in the 23-25psi range on the gauge at hot idle. But I am going to keep rocking it for at least a year (about 5 oil changes for me) to see what happens. I do track my gas mileage pretty closely on hwy trips, so i would notice a consistent improvement more than 0.5gpm or so.

Also looking at trying to get the valve stem seals replaced to kill the smoke show on a cold start...i might contract that out for the sake of time.
 

bucket

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Not in consumption, because I lose all my oil through the valve stem seals :).

I switched bc the oil pressure at hot idle was a little low compared to a few years ago. Used to idle around 28-30psi and was idling at 20-22psi this summer. After a couple oil change intervals, it does seem to be more in the 23-25psi range on the gauge at hot idle. But I am going to keep rocking it for at least a year (about 5 oil changes for me) to see what happens. I do track my gas mileage pretty closely on hwy trips, so i would notice a consistent improvement more than 0.5gpm or so.

Also looking at trying to get the valve stem seals replaced to kill the smoke show on a cold start...i might contract that out for the sake of time.

I'm assuming you have had the valve covers off and have verified that the oil drain back holes are clear?
 

bucket

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Simplest choice is to use 5 quarts of 10w30 full synthetic for an SBC. Even 10w30 Dino oil will work fine, but it will need to be changed more often. Cheapest source is usually the 5 quart jugs at Walmart.

Since you probably have a flat tappet cam, it really should have added ZDDP in the oil to protect the cam lobes from wear. Mobil 1 15w50 has 1300 ZDDP (compared to 800-900 in most of their other oil), but it’s a little harder to find in the store.

Axle is a lower priority. Ensure the fill hole bolt will come out (they can really stick), check the level in your axles first, and then make sure you have the right cover gaskets. Then take on the job of changing the axle gear oil. Check around the driveshaft seal for leaks.


Ok, another serious question now...

Where do you buy the Mobile 1 15w50? I have not noticed it in any of my local stores. But I also hadn't looked for it because I didn't know it existed.
 

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I'm assuming you have had the valve covers off and have verified that the oil drain back holes are clear?
Nope, but that's on my list of things to check....I suspect I may have a combination of slow drain back holes and bad seals. Maybe worth popping off the driver side cover and investigating. I think it comes off without having to get any accessories out of the way...
 

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