Does a 20w protect well enough for heavy towing?

[3Toyotas]

I've been running Amsoil ASM 0w20 in my tundra for 6k miles now, and i'm concerned whether or not it is protecting the motor like it should. I do plan on going extended OCI with the truck, but i want to be sure i'm using the right oil.
Can a 20w actually protect well enough for towing? Or should i consider going to a 30w like the ASL or the SSO?

The truck is an 07 tundra w/ the 5.7 all aluminum motor and has excellent cooling system's. ( Oil cooler, etc...)and never runs hot even on the hottest days towing 10k+.
The motor is highly technically advanced with 4 cams, dual vvti, and has 10 oil jets (i beleive)to name a few.

I know it's more critical with an aluminum block that it keeps plenty cool, and going off what i've read a 20w has better cooling properties than heavier weights, but at the expense of pretection, correct?

Any comments much appreciated.

P.S. UOA coming soon.

 

[mechtech2]

Do you have an oil temperature gauge?
Because, it's all about temperature.
If it gets too hot [like you surmise it may], a slightly thicker oil would be more suitable.
The Amsoil 0-30 would work very well in all conditions.
And there really is not a huge difference between your choices - it's not like you wanted to go to a 20-50.

 

[Gary Allan]

What does Toyota say? I would imagine that if they spec a 20 grade for all conditions, that the engine is well buffered for using it. Much like a SBC is fine using 5w-30 whether cruising along empty ..or towing fully loaded up 6% grades.

 

[3Toyotas]

Originally Posted By: mechtech2
Do you have an oil temperature gauge?
Because, it's all about temperature.
If it gets too hot [like you surmise it may], a slightly thicker oil would be more suitable.
The Amsoil 0-30 would work very well in all conditions.
And there really is not a huge difference between your choices - it's not like you wanted to go to a 20-50.


No, it don't have an oil temp guage just an idiot light.I would imagine with an 8 sump oil capacity it would be sufficient but i don't know. Especially since it has an oil cooler right up front.
That's what i've been thinking that it may be getting too hot due to the condition of the oil (black).

So the 30w wouldn't make that much of a difference?

 

[3Toyotas]

Originally Posted By: Gary Allan
What does Toyota say? I would imagine that if they spec a 20 grade for all conditions, that the engine is well buffered for using it. Much like a SBC is fine using 5w-30 whether cruising along empty ..or towing fully loaded up 6% grades.


Toyota has spec'd the engine for 0w20 or 5w20 but a 5w30 can be used but must be switched back at the next oil change (5k miles).

On the amsoil website, they recomend the 5w20 XL, 0w20 ASM, or the SS0 5w30 for the 5.7L motor.
I'd assume that means the SSO would do a fine job in the motor, correct? Better than the ASM though?

Being an amsoil guy, what's your take on it?

 

[3Toyotas]

Can it have something to do with break in metals since the truck only has 15k on it?

Going off a recent UOA on another tundra here (kd5byb user) with 22k on it now, it would lead me to beleive this to be the case. However, i am new to UOA and don't know a whole lot.

What wear metals show high that would corrolate the black oil condition at so low of miles?

 

[Gary Allan]

Quote:
So the 30w wouldn't make that much of a difference?



Does your oil cooler also have a coolantil exchanger in the system ..or is it straight from the engine to an up front airil raidiator?

If it has an exchanger in the mix, then your oil temps should never drift too much higher than normal as long as your coolant temp is in control.

SSO gives you up to 35k/one year extended drains. I, personally, can't see why other 30 grade offerings should be eliminated from the list (haven't researched it).

 

[TeeDub]

I'd run the SSO/0w-30 for heavy mountain towing, with a 15,000 mile max interval.

 

[ARB1977]

I wouldnt try to reinvent the wheel. Use what they say and call it a day.

 

[Fordiesel69]

Tow with 20wt and get a UOA. TBN will be down if oil got hot and any bearing metals will show if oil is too thin.

 

[aquariuscsm]

Originally Posted By: ARB1977
I wouldnt try to reinvent the wheel. Use what they say and call it a day.


That`s good advice. The manual or even better,if you can get an FSM,will always be your best resource. I use a 50wt oil for two reasons. My FSM recommends a 40 or 50wt oil if you do alot of sustained high speed driving and/or racing (which is what a sports car is made for) or if you live in a hot climate (I live in south Texas). My manual and FSM also does not recommend a 5W30 or 5W20,and says *not* to use either of these weights in the turbo model.

When in doubt,consult your manual/FSM.

 

[friendly_jacek]

Originally Posted By: 3Toyotas
I've been running Amsoil ASM 0w20 in my tundra for 6k miles now, and i'm concerned whether or not it is protecting the motor like it should.


You can call me paranoid, but I would not stray from toyota's required oil changes every 5000 to maintain warranty.

 

[3Toyotas]

Originally Posted By: Gary Allan
Quote:
So the 30w wouldn't make that much of a difference?



Does your oil cooler also have a coolantil exchanger in the system ..or is it straight from the engine to an up front airil raidiator?

If it has an exchanger in the mix, then your oil temps should never drift too much higher than normal as long as your coolant temp is in control.

SSO gives you up to 35k/one year extended drains. I, personally, can't see why other 30 grade offerings should be eliminated from the list (haven't researched it).


Yes, it has an oil exchanger in the mix and the coolant guage has never budged.

I don't know if the SSO would be worth the extra $ or not in my situation. ????
The truck is used for towing 95% of the time and i only put maybe 10-12k miles a year on it. So any oil i use will be dropped annually anyway. But if it's worth it, i'll pony up the doe.

I wouldn't think the ASL should be eliminated from the list, but you know your oil better than i do. I will say i'm extremely impressed with the ASL in my other rigs. I've got an 08 corolla running it with 12k on the oil now with almost no discoloration.
When i switched to ASL in our 08 gmc cargo van, it took away that 6.0L ticking noise completely.
So depending on my UOA, i may make a switch at the next OCI. I sure wish they'd hurry with it though. OAI..? must be pretty slow to get back results huh?

 

[3Toyotas]

Originally Posted By: TeeDub
I'd run the SSO/0w-30 for heavy mountain towing, with a 15,000 mile max interval.


Care to elaborate??

 

[3Toyotas]

Originally Posted By: ARB1977
I wouldnt try to reinvent the wheel. Use what they say and call it a day.


This is what i've thought since i got the truck, but i do think the CAFE situation has a lot to do with their visc.recomendation.

 

[3Toyotas]

Originally Posted By: Fordiesel69
Tow with 20wt and get a UOA. TBN will be down if oil got hot and any bearing metals will show if oil is too thin.


My UOA should be done by now. It'll be 2 weeks monday since i sent it off.

Good to know my TBN will waive a red flag for me. This helps me a lot simply because i know nothing about the metal counts and all that.

Thank you, i appreciate your help.

 

[3Toyotas]

Originally Posted By: friendly_jacek
Originally Posted By: 3Toyotas
I've been running Amsoil ASM 0w20 in my tundra for 6k miles now, and i'm concerned whether or not it is protecting the motor like it should.


You can call me paranoid, but I would not stray from toyota's required oil changes every 5000 to maintain warranty.


I'm not too concerned about the warrranty to be honest. I do however, replace the oem filter every 6mo/5000 with 1/2 qt. makeup oil. I'll be switching to wix when i run out of stock.

I want to get away from twice a year changes if i can. Just doesn't make much sense to me, especially with an 8 qt. sump. Doing the math, i think i'd be money ahead. Providing the oil can actually protect for that long.

 

[BuickGN]

It would not be a discussion for me. You're using the truck for 95% towing which means you're not going to notice the .00000001% mileage reduction and you're running it harder than most users so why not use a 30wt that you know will protect instead of wondering if you can get away with the 20wt.

 

[3Toyotas]

Originally Posted By: BuickGN
It would not be a discussion for me. You're using the truck for 95% towing which means you're not going to notice the .00000001% mileage reduction and you're running it harder than most users so why not use a 30wt that you know will protect instead of wondering if you can get away with the 20wt.


If it will actually protect any better, it'll be enough reason for me to make the switch.

Do you beleive there'll be enough of a noticable difference?

 

[Bryanccfshr]

There is more to protection than kinematic viscosity that is beyond most of us amateurs on this board.

I think the a 5w20 or 0w20 will work great in your application. With Toyota's outstanding cooling capacity and the coolant to oil heat exchanger your oil temperature is more controlled than most other light truck applications. Under heavy load that 20 wt will be as viscous as a 30 wt in a similar application without that Toyota oil cooler because the oil will remain controlled by the coolant temperature. That and the sump capacity, aluminum block and heads, the multiple oil squirters etc. make running a 20 wt as recommended a simple decision.