what oil

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Rinkle_Stinkle
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what oil

Post by Rinkle_Stinkle »

so after discovering my rings are wearing down some and I still have the tap I'm thinking maybe going with a heavier weighted oil with an additive and premium oil filter to see if that dampens the tap. I currently have 5 quarts of 10w-30 with the Lucas additive. after reading some I saw many run 15w-40 in their older AMC 360s and claim its a huge difference.

Thoughts?
repercussions?
etc...
1988 Grand Wag
AMC 360 with 96K
Edelbrock intake manifold
260H Comp Cam
Edelbrock AVS 4brl carb
Headman headers
2" to thrush muff with 3" tip exhaust

440sixpack
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Re: what oil

Post by 440sixpack »

Or 20w-50.

It depends, what temperatures ? how plugged up is your suction screen ? and if you're running a heavy additive do you need heavier oil ?

If you're not going to see super cold temps try a heavier weight and see what kind of pressure you run. if your tap is a wrist pin or something like that you won't notice any improvement.
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Rinkle_Stinkle
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Re: what oil

Post by Rinkle_Stinkle »

its pretty cold right now, single digits at night. I wont know about the screen as I haven't pulled the pan...

it currently has 5w-30 synthetic in it right now (not my decision) so I'm thinking to start with 10w-30 with the additive and see if it makes a difference. if it does then when it starts to warm I may go 15w or even 20w....
1988 Grand Wag
AMC 360 with 96K
Edelbrock intake manifold
260H Comp Cam
Edelbrock AVS 4brl carb
Headman headers
2" to thrush muff with 3" tip exhaust
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Stuka
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Re: what oil

Post by Stuka »

I run 10w30 in my current J10, and my old Cherokee (Which had a 360).

I fail to see how anybody could notice a "huge difference" between 10w30 and 15w40. That oil pressure gauge may show higher pressure, but this is actually a bad thing as it typically means more oil will be pushed out the pressure relief valve. Oil that is too thick can also cause bearings to have starved areas if the tolerances are too tight for the thicker oil.
2017 JKU Rubicon
Pevious Jeeps: 1981 J10, 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ

d4xycrq
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Re: what oil

Post by d4xycrq »

Rings don't usually tap - in my experience. Right now, with temperatures real low like yours Rinkle, I have one heck of a tap as my valve train clatters waiting for that thick oil to get up there for lubrication. Oil is too thick. My oil light is taking a longer time to go out, too. (no oil gauge...) Just topped up the oil with 5W30, and only tomorrow's start will tell.

Engine is a Buick 350 in a J Truck. Truck is still workin' for a livin'.

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letank
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Re: what oil

Post by letank »

X2 as above both posts

At this point, time to fix the issue and forget snake oil... Especially with single digit temp the 15w40 might be worse.
Michel
74 wag (349 Kmiles... parked, next step is a rust free body)
85 Gwag (229 Kmiles... the running test lab)
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Rinkle_Stinkle
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Re: what oil

Post by Rinkle_Stinkle »

i know the tap isn't the rings. its more than likely in the cylinder head. My plan is to do a rebuild or swap but the funds are available yet. I want to dampen the tap which is why I asked. I currently have 5 quarts of 10w-30 and an oil additive. I wasn't planning to go out in single digit temps to do a drive way oil change haha...

I do however appreciate your input and will keep that in mind moving forward.
1988 Grand Wag
AMC 360 with 96K
Edelbrock intake manifold
260H Comp Cam
Edelbrock AVS 4brl carb
Headman headers
2" to thrush muff with 3" tip exhaust

KJ Ryu
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Re: what oil

Post by KJ Ryu »

Might be worth it to pull the valve covers and check the torque on the rockers. Also, are you real sure that the tick isn't an exhaust leak?
Ron

2005 KJ, Hit-n-Run, 2am 6-17-2012, Totaled. :mad:
1977 SJ J10, 4v360, T18, D20, 37x14s, SOA & SF on tons, still ugly.
1978 SJ Wagoneer, 4v360, QT, 33x12.5s, lift by Sawzall :-bd NOT Running :(
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candymancan
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Re: what oil

Post by candymancan »

with these 0-10f winter temps id never ever run 15-40 lol.. your oil will be like cold honey when you first turn it on.. Hell 10-40 in 10f is very thick.

my wagoneer im trying out 0-40 from mobile 1. I like it so far.. The 0 makes its thinner for cold startups and to get lubrication where needed quick and the 40 helps me maintain 20psi on a very hot idle.. I like it better then 10-40 or 10-30 so far. I also got a bottle of rislone ZDDP like i have in all my engines.

Its just pretty darn expensive 26$ for 5 quart jug in walmart.

Exhaust leaks like mentioned can tick pretty loudely i have one that i have to seal with some kind of weld past e every 6 months until i can afford to pay a shop to do my manifolds. It sounds like a terrible lifter ticking when its blown and not plugged
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)
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Rinkle_Stinkle
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Re: what oil

Post by Rinkle_Stinkle »

I would imagine an exhaust leak wouldn't make an internal sound with a stethoscope on cylinder 1 though. When I listen to the engine I can hear it loud and clear under the valve cover.

I'm definitely going to wait for the temps to rise before doing an oil change. the whole reason I want to add heavier oil is to see if it dampens the tap because that will tell me more about where the tap is coming from.

Bottom line is it very well could be an exhaust leak, but if I add a slightly heavier weight of oil (in warmer weather) I would imagine that wont effect that and instead if it does dampen the sound then I know its eternal.

I definitely don't want to damager the engine further which is why I wanted to know the repercussions of adding a heavier weight and what that actually means.

I appreciate the explanations.

I believe what I will do is use the 10w-30 and add a little of the Lucas additive in and see what happens. if it makes a difference then i'll know what the next step is.
1988 Grand Wag
AMC 360 with 96K
Edelbrock intake manifold
260H Comp Cam
Edelbrock AVS 4brl carb
Headman headers
2" to thrush muff with 3" tip exhaust
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Rinkle_Stinkle
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Re: what oil

Post by Rinkle_Stinkle »

Ok so just learned something... I was told( not sure who) the the W meant weight.... I didn’t verify the information so I never discovered that was wrong. So now I understand what a 0w-40 could actually be better for my vehicle over a 10w-30 as the 0w would have more viscosity at lower temps, the 40 would be better because of the opposite, has more vicosity at running temp.

Am I understanding this correctly?
1988 Grand Wag
AMC 360 with 96K
Edelbrock intake manifold
260H Comp Cam
Edelbrock AVS 4brl carb
Headman headers
2" to thrush muff with 3" tip exhaust
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tgreese
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Re: what oil

Post by tgreese »

Can you run the engine with the valve cover off? In some cases, I think you can. The oil needs to run back to the crankcase as fast as it comes out of the valve train, so the drain holes need to be clear. There will be some splatter from the movement, so it will be a bit messy, but I'd try it. While running, you could push on the rocker to take up the slicak, and see if the noise changes.

There are other sources of noise, like piston slap and piston wrist pin. The valves train is more like a tick-tick since the relatively small size of the components makes the pitch of the noise rather high. Larger parts will have more of a thwack than a tick, and crank bearings being more of a muffled bang. The block will conduct noise, so your stethoscope doesn't do much more than isolate to specific cylinder, I would believe.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
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tgreese
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Re: what oil

Post by tgreese »

Rinkle_Stinkle wrote:Ok so just learned something... I was told( not sure who) the the W meant weight.... I didn’t verify the information so I never discovered that was wrong. So now I understand what a 0w-40 could actually be better for my vehicle over a 10w-30 as the 0w would have more viscosity at lower temps, the 40 would be better because of the opposite, has more vicosity at running temp.

Am I understanding this correctly?
No.

For example, a fresh 15W40 oil has the same viscosity as 15 weight single grade oil at 0C (freezing), and the same viscosity as 40 wt single grade at 100C (boiling). So the multivis oil thins out _less_ at high temps and thickens _less_ at low temps. But the oil still thickens and thins in response to temperature, just not as much as single grade.

The multivis oil wears out with age, losing its multivis character, becoming more like single grade (I'd guess closer to the higher number at all temps).
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.

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Re: what oil

Post by SJTD »

Gets thinner as the viscosity improvers break down.
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Cecil14
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Re: what oil

Post by Cecil14 »

In most multiviscosity oils, there are molecules that expand with temp. Like SJTD said, as those break down with time and use, the oil loses it's ability to "thicken" as the temps rise.


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Re: what oil

Post by rocklaurence »

My understanding is that the Wxx/xx is a reference to an oils viscosity resistance to change. So, its viscosity [resistance to flow] should remain the same within a set temperature range [10-40]. I am in the Hot/Humid South and run 15/40 in the AMCs with Zink additive. The Diesel 5qts are the least expensive. I do get less lifter tap at start up with the heavier oil.
Last edited by rocklaurence on Sat Feb 03, 2018 6:25 am, edited 1 time in total.

candymancan
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Re: what oil

Post by candymancan »

Rinkle_Stinkle wrote:Ok so just learned something... I was told( not sure who) the the W meant weight.... I didn’t verify the information so I never discovered that was wrong. So now I understand what a 0w-40 could actually be better for my vehicle over a 10w-30 as the 0w would have more viscosity at lower temps, the 40 would be better because of the opposite, has more vicosity at running temp.

Am I understanding this correctly?

No you got it backwords.. Viscous means thick.. how thick a fluid is. The 10 or 5 or 0 is how thick or in this case. how thin the oil is at 30f. The 40 is how thick the oil is when running at operating temperature. The lower numbers are based on temperatures at 30f i believe. And with these sub 10f temps im getting here where i live i opted to go for the 0-40 jist to try it. Plus mobile 1 in lab tests and tests by people on youtube has a much better pouring rate then other oil brands of the same thickness.. Like royal purple 10-30 vs mobile 1 10-30 the bottles on one test i believe were chilled to something like 0f and then flipped tigether on a little platform so they get flipped together.. And the royal purple was like honey.. And the mobile 1 flowed instantly.. The walmart brand didnt even come out lol.

So oil is not oil.. Even if they say 10-30 they are still different. After i saw these videos i was sold and tried to find 5-40 but i couldnt. But i did find mobile 1 0-40. Its a european formulated oil but so far with the zddp bittle i always use its been great.. The initial lifter tapping i had using my old oil is gone. My engine has a weird tapping it does when cold. I drive like half a mile and it goes away. When its very very cold in the winter the noise is even worse.

After getting this 0-40 the tapping is gone when i drive 15 feet and this is when the temps were 7f out. And when the engine is very hot and driven my oil pressure at idle in gear is 20psi and 55 driving Which means the 40 is doing its job. When i use 10-30 my oil pressure is more like 10 at hot idle in gear and about 45-50 driving.

so yes the low number is viscosity when cold. The high number is viscosity when hot. In cold temps you want a lower viscosity for initial startup and driving a cold engine.


20-50 is rediculously thick oil... I wouldnt use that oil unless i had litterally no oil pressure. In virgina it can be 90% humdity and 100f out.. In the summer i use 10-40.

Ppl might think im nuts for going 0-40 but its working great for me and my tapping in cold weather goes away in 10feet of taking off.. not 1.4 or half a mile like it used too.

Also some oils have better sheering resistance.. Meaning how well they stand up to sheer. The oil alot of people like using for some reason is that diesel oil called rotella. Its sheering resistance is terrible though and when the oil is tested for contaminants its actually really dirty oil compared to other brands. It also has very low levels of calcium.. Something gasoline engines need and diesel engines dont.

So why people put that junk in their gasoline engines is beyond me. Also rotella is not certified for gasoline engines anymore. Fyi calcium is a corrosion inhibitor gasoline combustion is very acidic so oils formulated for gasoline engines have high levels of calcium.. Diesel oils as i said have less of it. So in the end youre only harming your engine more by using a diesel oil.. specially when carburetors are known for dumping gasoline in the oil
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)
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Rinkle_Stinkle
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Re: what oil

Post by Rinkle_Stinkle »

what a wealth of knowledge. I appreciate everyone input! I'm actually taking the jeep to an engine shop this week to get another opinion on the cause of the tap. they will test compression and a multi list of other tests until they are sure they know the answer.

in ten years i'll probably know a hell of a lot more information and how to diagnose these kind of things but with the cold and lack of a garage and lack of knowledge I feel like I'm just not 100% qualified.

The shop said that when they diagnose it they will show me the ins and outs of diagnosing an engine so I will hopefully be able to do it myself in the future.
1988 Grand Wag
AMC 360 with 96K
Edelbrock intake manifold
260H Comp Cam
Edelbrock AVS 4brl carb
Headman headers
2" to thrush muff with 3" tip exhaust
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Stuka
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Re: what oil

Post by Stuka »

I see no issue with using a 0-40 in the winter when it is extremely cold, but I would switch to a 10w in the summer. The only downside to a 0w40 is that it will break down slightly faster. As the larger the difference between the two weights typically means it will break down faster than an oil with less of a difference.

Pretty much all newer vehicles use a 5w oil from the factory (My JK's have both used 5w20), but newer engines have tighter tolerances than our older engines.
2017 JKU Rubicon
Pevious Jeeps: 1981 J10, 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ

candymancan
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Re: what oil

Post by candymancan »

Stuka wrote:I see no issue with using a 0-40 in the winter when it is extremely cold, but I would switch to a 10w in the summer. The only downside to a 0w40 is that it will break down slightly faster. As the larger the difference between the two weights typically means it will break down faster than an oil with less of a difference.

Pretty much all newer vehicles use a 5w oil from the factory (My JK's have both used 5w20), but newer engines have tighter tolerances than our older engines.


Yea thats why i plan to drain it in the spring or summer and go back to 10-40. I know this mobile 1 can go like 10-15k miles on a oil change but i dont care. Im only using it for the winter. Its very very hard to find 5-40 oils only rotella diesel oil has that... And the 5-30 wont work because i dont like seeing 10psi oil pressure despite being told its fine. So i found these european oils are 0-40 and tried it and its been working out great actually.

The onllly downside is with my rear main seal is i had only replaced the lower seal ( i couldnt get the damn upper out) and while my oil leaks stopped using 10-40 oil after i replaced just the lower.. It leaks again with the 0-40 mobile 1.. It also leaks worse out of my leaking intake manifold front and back.

This year i really need to take the intake off and redo the gaskets.. And maybe try again for the rear main upper half. I just dont wanna nick the crank bashing it with a punch or dmg the seal and it still not coming out lol.
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)
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