Fluid Changes

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TX87R10

TX87R10

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Here is my recommendation - everyone wants you to use like 5w-20 but you know why? It is too gummy and leads to having to change it and I mean like every 5k miles... Most of us here use Grapeseed Oil mixed with vinegar instead of conventional motor oil. It provides better lubricity and the vinegar keeps things cleaned. If you hear a weird knocking after changing the oil try gassing it up to about 5k RPM to fix it.

I can't help you on the axels but I would drain the oil out of them. You don't want too much oil

If you need pictures of where to put the oil lmk
 
ali_c20

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TX87R10 said:
Here is my recommendation - everyone wants you to use like 5w-20 but you know why? It is too gummy and leads to having to change it and I mean like every 5k miles... Most of us here use Grapeseed Oil mixed with vinegar instead of conventional motor oil. It provides better lubricity and the vinegar keeps things cleaned. If you hear a weird knocking after changing the oil try gassing it up to about 5k RPM to fix it.

I can't help you on the axels but I would drain the oil out of them. You don't want too much oil

If you need pictures of where to put the oil lmk
Click to expand...
Another benefit of removing all the oil is that it reduces weight and gives you lower quarter mile times.
 
75gmck25

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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.
 
SquareRoot

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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:
 
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fast 99

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Yes, check oil condition in the axles and change if needed.

If it's been a while or you don't know the history a good idea to look inside for metal pieces. I have caught many diffs [that weren't noisy] before complete failure by pulling covers.
 
85K304SPD

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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...
 
squaredeal91

squaredeal91

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10w30, 30wt, 15w40, 20/50 oil, depending on application and temperature for these engines. Maybe try a couple. My friends 75 ford 360 runs better on 30wt than on 10w30. That might sound like bs but it's true. Switching to 30 actually made a difference in the way the engine sounded and it's smoothness.
Edit: How much oil? Depends on each and how long you let it drip. On our suburban normal oil change is 5 qts. If I let it drip all night it takes every bit of 6qts.
 
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