Oil Change Intervals

[Cracker4351]

What is a realistic interval for oil if you drive somewhat normally. I drive a 1995 Chev Silverado 2500 Cat 6.5TD. I have been using Rotella 15w-40 and change at 7000. I'm also thinking of using synthetic 5w-40 Rotella for Diesels, any info on that would also be appreciated.

[Mark Rinker]

1995 Chev Silverado 2500 Cat 6.5TD ? What is 'CAT' about your truck? CATalytic converters? CAThair seats? :)

Personally, I'd limit change intervals to 5K for conventionals, 10K for synthetics in non-dusty, average temperature condititions.

[EdHale]

I changed the oil religiously on my '98 at 3,000. It is still going strong after 265,000 (although my son in law drives it now). Ed

[Cracker4351]

"Cat" as in Caterpillar. Tha manufacturer of the engine, 6.5TD.

[jbplock]

Cracker,

Welcome to the Forums!

The GM 6.5 is a Detroit ... Here's a quote from content side of TheDieselPage.com (http://www.thedieselpage.com/) ...

"Designed as a diesel engine from the ground up by the Detroit Diesel Division of General Motors, the original 6.2L diesel engine was introduced in the 1982 model year GMC and Chevy C/K pickup truck and full-size SUV lines. Taking this engine design to the next level in the 1992 model year, the new 6.5L diesel engine was an advancement in technology, and was designed for the application of a turbocharger. The 6.2L saw its final year of production in 1993. While the 6.5 was replaced by the Duramax 6600 beginning in the 2001 model year Chevy and GMC vehicle production, the 6.5L diesel engine continues to be manufactured and sold by AM General. AM General is the manufacturer of the civilian H1 Hummer & military HMMWV. Not to worry, support for the 6.2/6.5 will continue to be a big part of The Diesel Page well into the future."

Regarding Oil Change Interval (OCI) for the 6.5TD, I think 7K is on the high side (my 2 cents ;) ) ... I used a 4Kmi OCI with AMSOIL 15w40 Synthetic in my 98 6.5TD ...UOA (Used Oil Analysis) results at this interval were good.. Rotella 15W40 or 5W40 may hold up for 7k but you might want to consider a UOA at 4 k then one at 7k to verify wear metals, soot, and and TBN are still within acceptable ranges..

Also check out BobIsTheOilGuy.com (http://theoildrop.server101.com/forums/ubbthreads.php)

:)

[Cracker4351]

Thanks for the info. I said Cat because the manifold cover has the cat logo on it. That's the plastic cover on the top of the engine where an air cleaner would normally go. I'm getting an oil analysis kit from blackstone labs and plan to have it analyzed. Thanks for the info!

[jbplock]

...the manifold cover has the cat logo on it...
...I'm getting an oil analysis kit from blackstone labs ...

Cracker,

Must be the previous owner liked CAT :)

Regarding UOA kits Blackstone is a good choice but their cost for TBN (or BN) Total Base Number is an extra $10. TBN is important parameter to test for, especially if you are considering an extended drain interval. TBN is a measure of the oil additive pack's ability to neutralize acid from the combustion process. Another option is www.AVLUBE.com (http://www.avlube.com/) ... Here's a link to AVLubes UOA Kit with TBN (http://www.avlube.com/fuankit.html)

(Hmmm... just noticed George's note on AVLUBE's site that TBN is less of a concern with ULSD ??? ... makes sense since sulphur in the fuel produces sulfuric acid ...)

:)

[Cracker4351]

The cover, I assumed, came with the engine. It has CAT on the side and Turbo Power on the top. Covers everything except the valve covers. Looks stock to me. Thanks for the link. I'll try them. I know you guys are laughing, that's cool!

[DmaxMaverick]

They've been called worse, but that's a Detroit under the hood. I have a couple "Turbo Power" covers in the barn somewhere. I'll have to take a closer look one of these days, but I don't remember seeing "CAT" on any of them I've seen. Snap a pic of it for us to see. It's interesting, for sure.

[Cracker4351]

Here is a pic of the infamous "CAT" cover! That sure looks like the CAT logo to me. Thanks for the help so far . I bet you guys thought I was smoking crack or something! lol.

[JeepSJ]

Looks like the previous owner was having some fun with paint.