Rebuilt 454 in motorhome, oil weight

[FlyNavyP3]

Originally Posted By: leroyd92
I think i know the answer to this. But I'm curios what you all think.

If you had a 454 with 40k on the engine, would you stay with 15w40?


The guage shows 30 psi oil pressure @ idle hot and 45/50 down the road


It depends, is your 454 fuel injected or carb? Open plains driving or mountain passes? In AZ I'd probably lean towards the 15w40 if it has a carb. I agree with the others that if it holds good oil pressure on 10w30 than that will also be sufficient.

 

[gfh77665]

Lets see...

AZ...454...Motorhome...

SAE 30 or 40 wt.

 

[Linctex]

My first choice: Synthetic HDEO 5w40 such as Rotella T6 (or Mobil or Delo)

Second choice: Mobil 1 15W-50

But honestly, my 454 (TBI) 1995 K3500 (4WD dually) has NOT had an easy life and has been fed a steady diet of whatever 15W-40 HDEO is on sale (Super Tech, TSC, Harvest King, etc.)..... 271,000 miles & never been apart.

 

[FlyNavyP3]

Originally Posted By: gfh77665
Lets see...

AZ...454...Motorhome...

SAE 30 or 40 wt.


I would've voted for an SAE 30 or SAE 40 but they're getting hard to find to be honest and finding top up oil on the road might be difficult. I agree in his use either of those would be exceptional choices. Heck my 4Runner and Lexus are both currently running SAE 30 oils here in Florida. With nighttime lows in the mid to upper 70's and daytime highs in the mid to low 90s I do see any reason to not run it. Especially for what I paid for it.

 

[scudpilot]

Amsoil Signature Series 10W30 all day long. Nothin better for that BB Bow tie.
If you want more Zinc use Z Rod 10W30. That thing will love it.

 

[userfriendly]

Go back to page one and look at BrocLuno's post.
What is your rod 'n main bearing clearance?
Did you use an oil pump shaft with a pinned steel collar & high volume pump?
Do you have an oil cooler? Truck size oil pan or larger?
I see a few posts I agree with on oil viscosity, but as Broc stated, it depends on a few variables.

 

[leroyd92]

Originally Posted By: userfriendly
Go back to page one and look at BrocLuno's post.
What is your rod 'n main bearing clearance?
Did you use an oil pump shaft with a pinned steel collar & high volume pump?
Do you have an oil cooler? Truck size oil pan or larger?
I see a few posts I agree with on oil viscosity, but as Broc stated, it depends on a few variables.


I didn't rebuild it.

 

[spasm3]

Originally Posted By: leroyd92
Originally Posted By: Alex_V
Originally Posted By: leroyd92
I'm going to check the oil level next time i make it to the house. Ill add 1 quart of marvel mystery oil to it ( if it's low ) and I'll see how it does.


Yes, why? Adding that much MMO seems more dangerous to me than stepping down to 10w30 and running it without keeping an eye on it.


I figured it would thin the oil out to 10w30ish range.

No other reason.

I did that to a batch of 20w50 one year in my bike. Burnt 2x times the oil.... Oil was a lot more thin in the jug. Bike did have more pep and ran a little cooler. I only saw 5psi oil pressure change



Don't mess with adding mmo, the eightys oil is gone. Adding that is adding an unknown variable, and will not necessarily be indicative of how a 10w 30 will behave in the engine. ( or better said, how the engine will behave with a 10w30).

 

[userfriendly]

If this was a 396 or 427, I would go along with the xW30 suggestions.
But a 454 with unknown bearing clearances, xW40, SAE 40 or 15W50.
High oil pressure is good, 60 PSI+, not for the bearings, but for valve train oiling.
Some machine shops like to drill a little hole in the front oil gallery plug for the timing chain.

 

[FCD]

If it's an unrebuilt, flat tappet early gen 454 in a motorhome in Arizona, Shell Rotella 15W-40 or Delo 400 15W-40 would be just fine, if it burns oil just add oil as needed and don't worry.
Even Delo 400 Straight 40 would be just fine.

 

[gfh77665]

Originally Posted By: FlyNavyP3
Originally Posted By: gfh77665
Lets see...

AZ...454...Motorhome...

SAE 30 or 40 wt.


I would've voted for an SAE 30 or SAE 40 but they're getting hard to find to be honest and finding top up oil on the road might be difficult. I agree in his use either of those would be exceptional choices..


Another fine choice for AZ would be a 20w-50 in this application, if he cant fine SAE 30 or SAE 40.

 

[leroyd92]

I found out today the shop who had the motor rebuilt said to run 15w40.

I know to a lot of you that won't mean much as its hear say, but being it was rebuilt in California and is up to date on smog it makes me feel like things motor might be on the loose side.

Current oiil has less then 1k on it but is a few years old

 

[CT8]

Big blocks aren't built on the loose side that is what the clearances are. They like 40 wts. I used to fun a flat bottom drag boat and the clearances were always factory and they did best with a 40 or 20W-50. On disassemble the valve train and cam would be wasted from the cam and high valve spring pressure but the crank and rod bearings and bores would be fine. These were 7,500 rpm engines

 

[CT8]

Originally Posted By: userfriendly
Go back to page one and look at BrocLuno's post.
What is your rod 'n main bearing clearance?
Did you use an oil pump shaft with a pinned steel collar & high volume pump?
Do you have an oil cooler? Truck size oil pan or larger?
I see a few posts I agree with on oil viscosity, but as Broc stated, it depends on a few variables.
I would put money on the clearance are what every builder uses for BBC engines. The factory clearances, as that is what works.

 

[userfriendly]

A little crank harmonics, rod 'n block flexing, add a little pre-ignition and what was .0025" on the rods is now .001" or streaked.
How does .002" mains 'n .0025" rods sound?

 

[leroyd92]

Originally Posted By: userfriendly
A little crank harmonics, rod 'n block flexing, add a little pre-ignition and what was .0025" on the rods is now .001" or streaked.
How does .002" mains 'n .0025" rods sound?



Are you saying thinner is better?

 

[BrocLuno]

Originally Posted By: userfriendly
A little crank harmonics, rod 'n block flexing, add a little pre-ignition and what was .0025" on the rods is now .001" or streaked.
How does .002" mains 'n .0025" rods sound?


Sounds fine to me. With those numbers I'd run a stout xW-30 something and be quite happy

My thinking was that the shop that rebuilt it was re-using the OEM crank as it came out and installing replacement bearings with just a few mic readings. At 40K when it went in, it would have some wear on the journals, so might have opened up a bit ... And the builders reply to run 15W-40 leads me to think this is just what they did. So my guess is they are out around 0.003" now. A 40 will be happy in there

 

[leroyd92]

Thank you for clearing that up for me I'm not am engine builder.

My friend just told me he typically used 1qt every 4500 miles. So it seems like the motor is happy with. 15w40

 

[CT8]

Originally Posted By: leroyd92
Thank you for clearing that up for me I'm not am engine builder.

My friend just told me he typically used 1qt every 4500 miles. So it seems like the motor is happy with. 15w40
Yes and 15W-50 works well .

 

[CT8]

Originally Posted By: userfriendly
A little crank harmonics, rod 'n block flexing, add a little pre-ignition and what was .0025" on the rods is now .001" or streaked.
How does .002" mains 'n .0025" rods sound?
Factory! or Close the last BBC I built was in 2000! BBC is my favorite engine.