1995 Chevrolet K2500 6.5 diesel - viscosities?

Status
Not open for further replies.
Joined
Mar 1, 2010
Messages
797
Location
Finland
Hello.

My buddy has the above mentioned non-turbo 6.5 diesel K2500. According the manual it specifies 15W-40 for year around use and if very cold in the winter then 5W-40 can be used.

Manual says the following:

"Chevrolet states that you should not use 10W-30, 10W-40 or 20W-50 oils in your 6.5 diesel engine."

I do not get why the 10W-40 could be harmful as they allow 5W-40. For him the year around use of 10W-40 HDEO would be optimum as that's what his other car uses.

Any ideas on the subject?

What about 5W-40 HDEO year around?
 
Because in 1995, the 10W40s on the market did not meet the diesel specs that Chevy required.

Viscosity is only part of the requirement...

I am not familiar with any 10W40 HDEOs that meet the diesel specs...so I would go with a 5W40, like Rotella T6, in a cold climate, or a 15W40, like Rotella, in a warmer one.

There are lots of good 15W40s out there, don't overthink this...

And a 5W40 HDEO (not just any 5W40) would be a great choice year 'round...
 
Amsoil's 25k 10W-40 (AME?) probably has the diesel specs for an engine that old.

There aren't a LOT of 10W-40 HDEO's - about the only manufacturer that makes a lot of them is Petro-Canada - they have a couple of good 10W-40 HDEO's.

Rotella 5W-40 would be a great, easy to get choice.
 
I should have put it this way: I am not familiar with any 10W40 HDEOs....period...

Are we using the word the same way?

Heavy Duty Engine Oil...as in diesel...HDEOs are generally OK to use in gas engines...but not the other way around...

Now, Shell makes a 10W30 HDEO...but the manual states not to use that viscosity...so, additive package would be good...but the viscosity would not...
 
Where are you (or your buddy) located?

Do you need a thinner oil, or will 15w-40 work?
I don't understand how a 10w-40 would be optimum, but a 15w-40 is being ruled out. There simply isn't that much difference.

If you're in the states, and near a farming community, then there is T5 semi-syn in 10w-40 at many farm supply stores.
 
I am shocked a manual from 1995 even menthions a 5w-40...I would have thought it would have mentioned 15w40 and SAE 30!

Given the high compression 20:1+, if you have descent glowplugs, batteries and starter..you should have no issue with a 15w40 in some pretty cold weather, assuming you live south of artic circle.

My quess is they were concerned about people running non-API C rated (such as CI or CJ-4) oil in the truck.
 
Depends on how cold it gets where you live-I've had Delo 400 straight SAE 30 in my '93 GMC non-turbo 6.2 diesel for around 5-6 years now, year-round, starts without being plugged in-BUT if I ever have to start it below 0F I put a magnetic oil pan heater on it for 3-4 hours first. My experience is any quality HDEO/diesel rated oil will work well in a 6.2 or 6.5-they're not very hard on oil.
 
Originally Posted By: dnewton3
Where are you (or your buddy) located?

Do you need a thinner oil, or will 15w-40 work?
I don't understand how a 10w-40 would be optimum, but a 15w-40 is being ruled out. There simply isn't that much difference.

If you're in the states, and near a farming community, then there is T5 semi-syn in 10w-40 at many farm supply stores.


I agree except I've never seen t5 in anything except 10w30 and its usually 2-3$ less than t6 5w40.(per gallon)


15w40 -- spring summer fall... 5w40 late fall to early spring.

if you filled in your location we could give better advice

not sure if you are wintering in texas florida or alaska.
 
Last edited:
Originally Posted By: Rand


I agree except I've never seen t5 in anything except 10w30 and its usually 2-3$ less than t6 5w40.(per gallon)



I'm, in MW Ohio too. Where are you seeing T6 5W40 for less that $20/qt. I want to shop there.
 
Last edited:
Thanks gents for the comments.

The 15W-40 would not be a concern but up here in the North it gets sub 0 degrees Fahrenheit.

We have at least following API CI-4 or such diesel rated 10W-40 mineral or semisynthetics available

Mobil Delvac 10W-40
Teboil Super HPD 10W-40
Neste Turbo LXE 10W-40

Shell Rotella is not available but the Rimula range is

Shell Rimula oils

In any case, thank you for the information. I believe he will switch to a 10W-40 for the rest of the winter.
 
Had a 95 pickup and a 99 suburban both with 6.5 turbo and always ran 15-40 year round.Worked here outside of Chicago. ran 5 to 8k oci with rotella and napa gold.
 
Well, update after a year on this subject:

K2500 has been sitting for almost two years now and my buddy made me buy it from him today.
grin.gif


chevyk2500.jpg
 
Nice buy there !!!


Bo

Originally Posted By: Finn
Well, update after a year on this subject:

K2500 has been sitting for almost two years now and my buddy made me buy it from him today.
grin.gif


chevyk2500.jpg
 
Thank you. Will see what sort of money pit it will be.
grin.gif


He has been using Finnish Neste Turbo LXE in it. Do you guys see anything "wrong" with the characteristics?


NESTE TURBO LXE 10W-40, 15W-40
Multigrade diesel engine oil


SAE 10W-40 synthetic, SAE 15W-40 mineral


Neste Turbo LXE is developed for heavy-duty truck professionals. It is especially suitable for of heavy-duty vehicles and construction machines engines with extended oil change intervals and can also use in passenger cars and vans with gasoline or diesel engines.

Neste Turbo LXE exceeds the requirements of the new API CI-4 and ACEA E7 standards and meets also the requirements of low emission engines Euro 3, Euro 4 and engines with EGR. Oil guarantees good engine cleanliness, a high degree of protection against wear and low oil consumption.

Neste Turbo LXE meets the quality requirements of modern highly advanced heavy-duty engines and car manufactures. Check engine oil requirements and oil change intervals from owner's manual.

Synthetic Neste Turbo LXE 10W-40 allows for excellent cold operation and wide viscosity range. It has a wide viscosity range so it can be used year-around and also avoid seasonal oil changes.



nesteturbolxe.jpg
 
That's good to hear, much obliged.

We changed today
- front diff Mobilube HD 80W-90 API GL5
- rear diff Mobilube HD 80W-90 API GL5
- transfer case Gulf Dexron III
- engine Neste Turbo LXE 15W-40

My plan is to use said 15W-40 in the summer and 10W-40 in coldest winter period.
 
Biggest thing I would do on a '95 6.5 is relocate the PMD (circuit board on the injection pump) to a separate remote mounted heat sink-if it hasn't been done already. Engine heat causes the electronics to fail on them.
 
Thanks for the tip. Will need to investigate this matter a bit to see where I can get the extension cable or if it is easy to make ourselves.
 
I'm almost certain Rotella T5 was available in 10w-30 and 10w-40. I read spec sheets on them. But I've never seen the 40 in any store. GM says don't use those viscosity oils because at that time most of them were non diesel rated oils. A 10w-30 HDEO would be perfect in a 6.5L. Especially since it's not a super powerful diesel anyhow. It's more like a gas engine than a diesel.
 
Status
Not open for further replies.
Back
Top