I moved to a 30 grade in my wife's Focus to help slow the consumption it had on a 20 grade. It worked.
Heavier Weight for Older Engines?
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making a blanket statement to answer your question is the wrong approach. As a few answers stated it is all about hot oil pressure and bearing clearances. And guess what all the bearing don't necessarily have the same clearances on a high mileage engine. If only 1 bearing has a larger amount of wear the oil pressure drop there will cause low pressure on other surrounding bearings as well and the problem spreads. going up in weight is cheap insurance against loss of pressure in an old engine with minimal downside.
Originally Posted by BrocLuno
To me, it's all about the rod bearing clearances. The rods started out at 0.0025" or so. By 200K they are at 0.005" for sure. Replacement clearances are usually at around 0.006"+. A 20 grade is having some issues filling that void at high temps.)
Do we have evidence that bearing clearances tend to increase so many ten thousandths after 100K or 200K miles as suggested? I would think those in the engine re-building business would know. I've never read anything to suggest there might be a linear relationship of bearing clearance vs. engine mileage.
Also, why would replacement bearings be sized to be twice what the new engine spec was? That doesn't seem reasonable - but I've never had engines rebuilt ? I thought that was why one uses Plastigauge to help pick the bearing replacement that gets one back toward the desired clearances e.g. 0.0025" .
To me, it's all about the rod bearing clearances. The rods started out at 0.0025" or so. By 200K they are at 0.005" for sure. Replacement clearances are usually at around 0.006"+. A 20 grade is having some issues filling that void at high temps.)
Do we have evidence that bearing clearances tend to increase so many ten thousandths after 100K or 200K miles as suggested? I would think those in the engine re-building business would know. I've never read anything to suggest there might be a linear relationship of bearing clearance vs. engine mileage.
Also, why would replacement bearings be sized to be twice what the new engine spec was? That doesn't seem reasonable - but I've never had engines rebuilt ? I thought that was why one uses Plastigauge to help pick the bearing replacement that gets one back toward the desired clearances e.g. 0.0025" .
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Patman
Staff member
Originally Posted by ProjectCommuter
Im a lurker, I read a lot to learn on a lot of forums. ;-)
Glad to see you dipped your toes in the water, feel free to be more vocal now that you've broken your silence
Im a lurker, I read a lot to learn on a lot of forums. ;-)
Glad to see you dipped your toes in the water, feel free to be more vocal now that you've broken your silence
Originally Posted by Cressida
Originally Posted by BrocLuno
To me, it's all about the rod bearing clearances. The rods started out at 0.0025" or so. By 200K they are at 0.005" for sure. Replacement clearances are usually at around 0.006"+. A 20 grade is having some issues filling that void at high temps.)
Do we have evidence that bearing clearances tend to increase so many ten thousandths after 100K or 200K miles as suggested? I would think those in the engine re-building business would know. I've never read anything to suggest there might be a linear relationship of bearing clearance vs. engine mileage.
I have almost 200,000 on my 4.6 F150, and I know for a fact the rod bearing clearances are nowhere near .005" .... That is HUGE (comparatively)
I have never torn apart my 454/7.4 in my K3500 with 296,000 miles, but I know those rod bearings aren't at .005", either.
Originally Posted by BrocLuno
To me, it's all about the rod bearing clearances. The rods started out at 0.0025" or so. By 200K they are at 0.005" for sure. Replacement clearances are usually at around 0.006"+. A 20 grade is having some issues filling that void at high temps.)
Do we have evidence that bearing clearances tend to increase so many ten thousandths after 100K or 200K miles as suggested? I would think those in the engine re-building business would know. I've never read anything to suggest there might be a linear relationship of bearing clearance vs. engine mileage.
I have almost 200,000 on my 4.6 F150, and I know for a fact the rod bearing clearances are nowhere near .005" .... That is HUGE (comparatively)
I have never torn apart my 454/7.4 in my K3500 with 296,000 miles, but I know those rod bearings aren't at .005", either.
I ran my fusion on 5w-20 for the first 100k of its life, bumped up to 5w30 to reduce consumption and ended up settling on Mobil 1 High Mileage 10w30 when I moved back to FL.
I'm a thick oil guy, I prefer non-ILSAC 30 or one of the 0w-40 for most applications. 0w-20s also do the job but you get more insurance against dilution and shear by going with a heavier grade.
Really it's more about what will let you sleep at night. The engine doesn't care unless you're racing or towing. Run the Mobil 1 High Mileage 5w30 in everything and forget about it. Take advantage of the mail in rebates
I'm a thick oil guy, I prefer non-ILSAC 30 or one of the 0w-40 for most applications. 0w-20s also do the job but you get more insurance against dilution and shear by going with a heavier grade.
Really it's more about what will let you sleep at night. The engine doesn't care unless you're racing or towing. Run the Mobil 1 High Mileage 5w30 in everything and forget about it. Take advantage of the mail in rebates
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My 2000 Rangers 4.0L has 298k on it, it doesn't use oil or leak. I'be been using 5w30 in it every 3K but lately the oil pressure at hot idle has been dipping lower... at a stop sign today I noticed it was below 20psi. While driving hot its around 40-50, when its cold it holds fine at 50-60.
Then.... I saw it floating around 18psi hot while I was parked later today.... so I got a jug of 10w40 and a filter. If that doesn't help the hot idle oil pressure I might go up to 10w50 come warm weather.
From reading here on BITOG that seems to be a logical and safe direction to go.
Then.... I saw it floating around 18psi hot while I was parked later today.... so I got a jug of 10w40 and a filter. If that doesn't help the hot idle oil pressure I might go up to 10w50 come warm weather.
From reading here on BITOG that seems to be a logical and safe direction to go.
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Your oil pressures are great! 10psi per 1k engine rpm is the standard so if your engine idles at 1k rpm anything over 10psi is fine.
Originally Posted by ka9mnx
Your oil pressures are great! 10psi per 1k engine rpm is the standard so if your engine idles at 1k rpm anything over 10psi is fine.
This rule applies to a SBC. But at 20PSI for a Ford 4.0 is fine at hot idle it shows really insignificant bearing wear. Is this with the factory gage?
Your oil pressures are great! 10psi per 1k engine rpm is the standard so if your engine idles at 1k rpm anything over 10psi is fine.
This rule applies to a SBC. But at 20PSI for a Ford 4.0 is fine at hot idle it shows really insignificant bearing wear. Is this with the factory gage?
I've been going back and forth for a while about my 2007 Tacoma. 206K on it now. Been using Mobil 1 Extended Performance 5w30/Fram Ultra forever now, at 10K OCIs, and it uses no oil and runs great. Thinking about going to the new Mobil 1 Extended Performance-HM 10w30 on next fill, same OCI.
Most of my driving is at 75-90 mph, freeway. I do idle the engine for about an hour per week.
Most of my driving is at 75-90 mph, freeway. I do idle the engine for about an hour per week.
Originally Posted by john_pifer
I've been going back and forth for a while about my 2007 Tacoma. 206K on it now. Been using Mobil 1 Extended Performance 5w30/Fram Ultra forever now, at 10K OCIs, and it uses no oil and runs great. Thinking about going to the new Mobil 1 Extended Performance-HM 10w30 on next fill, same OCI.
Most of my driving is at 75-90 mph, freeway. I do idle the engine for about an hour per week.
Either one will work just fine but why the EP? I think HM 10w30 EP is a little overkill.
I've been going back and forth for a while about my 2007 Tacoma. 206K on it now. Been using Mobil 1 Extended Performance 5w30/Fram Ultra forever now, at 10K OCIs, and it uses no oil and runs great. Thinking about going to the new Mobil 1 Extended Performance-HM 10w30 on next fill, same OCI.
Most of my driving is at 75-90 mph, freeway. I do idle the engine for about an hour per week.
Either one will work just fine but why the EP? I think HM 10w30 EP is a little overkill.
Originally Posted by dave1251
Originally Posted by ka9mnx
Your oil pressures are great! 10psi per 1k engine rpm is the standard so if your engine idles at 1k rpm anything over 10psi is fine.
This rule applies to a SBC. But at 20PSI for a Ford 4.0 is fine at hot idle it shows really insignificant bearing wear. Is this with the factory gage?
10psi per 1k rpm is an engine builders standard for any American (gas) iron engine. Diesels excluded. 4psi hot idle was the spec for 2 cycle Detroit Diesels with 20psi at rpm and that was with a straight 40. In my 30 years working on them I always saw 10psi at idle and 40psi at rpm. GPM was more important than psi.
Originally Posted by ka9mnx
Your oil pressures are great! 10psi per 1k engine rpm is the standard so if your engine idles at 1k rpm anything over 10psi is fine.
This rule applies to a SBC. But at 20PSI for a Ford 4.0 is fine at hot idle it shows really insignificant bearing wear. Is this with the factory gage?
10psi per 1k rpm is an engine builders standard for any American (gas) iron engine. Diesels excluded. 4psi hot idle was the spec for 2 cycle Detroit Diesels with 20psi at rpm and that was with a straight 40. In my 30 years working on them I always saw 10psi at idle and 40psi at rpm. GPM was more important than psi.
Originally Posted by ka9mnx
Originally Posted by john_pifer
I've been going back and forth for a while about my 2007 Tacoma. 206K on it now. Been using Mobil 1 Extended Performance 5w30/Fram Ultra forever now, at 10K OCIs, and it uses no oil and runs great. Thinking about going to the new Mobil 1 Extended Performance-HM 10w30 on next fill, same OCI.
Most of my driving is at 75-90 mph, freeway. I do idle the engine for about an hour per week.
Either one will work just fine but why the EP? I think HM 10w30 EP is a little overkill.
Why do you say that?
Originally Posted by john_pifer
I've been going back and forth for a while about my 2007 Tacoma. 206K on it now. Been using Mobil 1 Extended Performance 5w30/Fram Ultra forever now, at 10K OCIs, and it uses no oil and runs great. Thinking about going to the new Mobil 1 Extended Performance-HM 10w30 on next fill, same OCI.
Most of my driving is at 75-90 mph, freeway. I do idle the engine for about an hour per week.
Either one will work just fine but why the EP? I think HM 10w30 EP is a little overkill.
Why do you say that?
The subject is heavier grade (weight) for older engines.
Mobil1 EP HM 10w30
KV@100C 10.2
KV@40C 63.7
HTHS 3.1
Mobil 1 High Mileage 10w30
KV@100C 12.1
KV@40C 78
HTHS 3.5
Mobil 1 High Mileage 10w30 is clearly the heavier oil and probably less expensive.
Mobil1 EP HM 10w30
KV@100C 10.2
KV@40C 63.7
HTHS 3.1
Mobil 1 High Mileage 10w30
KV@100C 12.1
KV@40C 78
HTHS 3.5
Mobil 1 High Mileage 10w30 is clearly the heavier oil and probably less expensive.
BTW I don't see why the vanilla Mobil 1 wouldn't fulfill your 10k OCI requirements.
Originally Posted by Linctex
Originally Posted by Cressida
Originally Posted by BrocLuno
To me, it's all about the rod bearing clearances. The rods started out at 0.0025" or so. By 200K they are at 0.005" for sure. Replacement clearances are usually at around 0.006"+. A 20 grade is having some issues filling that void at high temps.)
Do we have evidence that bearing clearances tend to increase so many ten thousandths after 100K or 200K miles as suggested? I would think those in the engine re-building business would know. I've never read anything to suggest there might be a linear relationship of bearing clearance vs. engine mileage.
I have almost 200,000 on my 4.6 F150, and I know for a fact the rod bearing clearances are nowhere near .005" .... That is HUGE (comparatively)
I have never torn apart my 454/7.4 in my K3500 with 296,000 miles, but I know those rod bearings aren't at .005", either.
Then you bought these new and have taken good care of them. Older engines with unknown service history prior to present ownership can often have subtle rod knock on cold start and low idle pressure and when you open them up (when they finally give up the ghost), they are between 0.004~6 and showing some copper ... Yours are tight, I have a couple of loose ones, all because the PO pulled a boat and did not really service the engines. I'll do short blocks next year (already have rebuilt heads waiting).
Every case is different. I tore down a running BBC once that we threw crank away because it was so bad. The whole bottom end was showing copper. It had obviously had a coolant leak at some point and the bearings were trashed. You just never know ...
Originally Posted by Cressida
Originally Posted by BrocLuno
To me, it's all about the rod bearing clearances. The rods started out at 0.0025" or so. By 200K they are at 0.005" for sure. Replacement clearances are usually at around 0.006"+. A 20 grade is having some issues filling that void at high temps.)
Do we have evidence that bearing clearances tend to increase so many ten thousandths after 100K or 200K miles as suggested? I would think those in the engine re-building business would know. I've never read anything to suggest there might be a linear relationship of bearing clearance vs. engine mileage.
I have almost 200,000 on my 4.6 F150, and I know for a fact the rod bearing clearances are nowhere near .005" .... That is HUGE (comparatively)
I have never torn apart my 454/7.4 in my K3500 with 296,000 miles, but I know those rod bearings aren't at .005", either.
Then you bought these new and have taken good care of them. Older engines with unknown service history prior to present ownership can often have subtle rod knock on cold start and low idle pressure and when you open them up (when they finally give up the ghost), they are between 0.004~6 and showing some copper ... Yours are tight, I have a couple of loose ones, all because the PO pulled a boat and did not really service the engines. I'll do short blocks next year (already have rebuilt heads waiting).
Every case is different. I tore down a running BBC once that we threw crank away because it was so bad. The whole bottom end was showing copper. It had obviously had a coolant leak at some point and the bearings were trashed. You just never know ...
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Originally Posted by ka9mnx
The subject is heavier grade (weight) for older engines.
Mobil 1 Extended Performance High Mileage 10w30
KV@100C 10.2
KV@40C 63.7
HTHS 3.1
Mobil 1 High Mileage 10w30
KV@100C 12.1
KV@40C 78
HTHS 3.5
Mobil 1 High Mileage 10w30 is clearly the heavier oil and probably less expensive.
Originally Posted by ka9mnx
BTW I don't see why the vanilla Mobil 1 wouldn't fulfill your 10k OCI requirements.
You'd said EP was overkill for my application; I was wondering why. Mobil 1 guarantees the EP formula to protect for 15,000 miles, where they make no such guarantee for the standard formulation. There have been times (in fact, it's common) that I go a few hundred miles over 10,000 before I have a chance to do an oil change. I like the cushion that EP provides. Additionally, the EP variant contains more PAO, which I also like.
In the last couple of years, I've also become a fan of 10w30 oils as compared to 5w30, due to a lot of research I've done due to owning my WRX.
10W-30s tens to be more shear-stable, more resistant to dilution, and have better NOACK ratings than 5w30s.
I've just used the Mobil 1 Extended Performance 5w30 for so long, and the truck has run so well on it, that I've seen no reason to switch.
But now that there is an High Mileage version of EP, it's got me thinking, since 206K in the truck...
IMHO, Mobil 1 oils are one of the best value oils on the market.
The subject is heavier grade (weight) for older engines.
Mobil 1 Extended Performance High Mileage 10w30
KV@100C 10.2
KV@40C 63.7
HTHS 3.1
Mobil 1 High Mileage 10w30
KV@100C 12.1
KV@40C 78
HTHS 3.5
Mobil 1 High Mileage 10w30 is clearly the heavier oil and probably less expensive.
Originally Posted by ka9mnx
BTW I don't see why the vanilla Mobil 1 wouldn't fulfill your 10k OCI requirements.
You'd said EP was overkill for my application; I was wondering why. Mobil 1 guarantees the EP formula to protect for 15,000 miles, where they make no such guarantee for the standard formulation. There have been times (in fact, it's common) that I go a few hundred miles over 10,000 before I have a chance to do an oil change. I like the cushion that EP provides. Additionally, the EP variant contains more PAO, which I also like.
In the last couple of years, I've also become a fan of 10w30 oils as compared to 5w30, due to a lot of research I've done due to owning my WRX.
10W-30s tens to be more shear-stable, more resistant to dilution, and have better NOACK ratings than 5w30s.
I've just used the Mobil 1 Extended Performance 5w30 for so long, and the truck has run so well on it, that I've seen no reason to switch.
But now that there is an High Mileage version of EP, it's got me thinking, since 206K in the truck...
IMHO, Mobil 1 oils are one of the best value oils on the market.
Ok John. If the EP makes you feel better about the additional mileage then that is what you should use. I'm planning to go at least 10k on the vanilla. We'll see how that works out!
Originally Posted by dave1251
Originally Posted by ka9mnx
Your oil pressures are great! 10psi per 1k engine rpm is the standard so if your engine idles at 1k rpm anything over 10psi is fine.
This rule applies to a SBC. But at 20PSI for a Ford 4.0 is fine at hot idle it shows really insignificant bearing wear. Is this with the factory gage?
It's a new aftermarket standard gauge. I have it tapped into the oil sensor port on the block. It idles at around 850-950 when its hot.
That's nice to know, if 18-20psi at hot idle is good for a ford 4.0L pushrod engine I won't worry so much about it. It's a few miles from 300K so I'm trying to make it last a while longer.
It has a quiet intermittent knock, that seems every now and then to be only when you shift out of park and sit there at idle with the brake on. That little bit of a load makes it knock (albeit a very quiet knock) and it goes away as soon as you move out. Every time a I hear it, and get out to look where its coming from it's gone. I'm going to assume a real rod knock would be a constant thing and get worse with acceleration? Maybe its not a rod at all... just an old engine noise.... a sticky lifter maybe...
Otherwise it runs quiet and smooth.
Originally Posted by ka9mnx
Your oil pressures are great! 10psi per 1k engine rpm is the standard so if your engine idles at 1k rpm anything over 10psi is fine.
This rule applies to a SBC. But at 20PSI for a Ford 4.0 is fine at hot idle it shows really insignificant bearing wear. Is this with the factory gage?
It's a new aftermarket standard gauge. I have it tapped into the oil sensor port on the block. It idles at around 850-950 when its hot.
That's nice to know, if 18-20psi at hot idle is good for a ford 4.0L pushrod engine I won't worry so much about it. It's a few miles from 300K so I'm trying to make it last a while longer.
It has a quiet intermittent knock, that seems every now and then to be only when you shift out of park and sit there at idle with the brake on. That little bit of a load makes it knock (albeit a very quiet knock) and it goes away as soon as you move out. Every time a I hear it, and get out to look where its coming from it's gone. I'm going to assume a real rod knock would be a constant thing and get worse with acceleration? Maybe its not a rod at all... just an old engine noise.... a sticky lifter maybe...
Otherwise it runs quiet and smooth.
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