Engine/Transmission (1998.5 - 2002) Oil for cold climate

[leathermaneod]

Hi all,

I have been reading up on oil statistics and trying to decide on the best choice for my 01 cummins with 251,000 miles for the winter here in Watertown, NY(30 miles from the canada border). I have read that the biggest reason for using synthetic is either to extend change intervals, or for extreme temperatures. I have no intention of extending my drain interval, which is currently approx. 3000 miles with Rotella T 15w40 and Fleetguard LF16035. I know a lot of you are about to tell me I'm wasting good oil but I make multiple short trips per day (less than 10 miles), and I want to follow the B maintenance schedule in my owners manual. I am wondering if the temps I will be seen up here count as extreme. Last year it didn't get above 0 much if at all from about the end of December the the end of February, and during that time it got as low as -20 IIRC. I have been thinking about switching to a synthetic blend for the winter. Such as Rotella T5 in 15w40, or going to a full synthetic such as Valvoline Premium Blue Extreme in 15w40. My concerns with synthetic and synthetic blend are that it will cause problems since the truck has 251,000 miles. Also, I am not sure if it will be cold enough here to make it completely necessary to make the switch. I will be plugging the truck in as much as possible, but I don't think I will be able to during the day at work. I recently read a study done by TDR that indicated that Rotella T is on the low end as far as soot control, while Valvoline Premium Blue is on the high end. I will most likely be switching to the VPB over the Rotella T even if I don't switch to synthetic. You can find the study here https://www.turbodieselregister.com/tdrarticles/tdrarticle56_lubeoilspecs.html.

What are your thoughts?

 

[RonaldLarson]

Hi all,

I have been reading up on oil statistics and trying to decide on the best choice for my 01 cummins with 251,000 miles for the winter here in Watertown, NY(30 miles from the canada border). I have read that the biggest reason for using synthetic is either to extend change intervals, or for extreme temperatures. I have no intention of extending my drain interval, which is currently approx. 3000 miles with Rotella T 15w40 and Fleetguard LF16035. I know a lot of you are about to tell me I'm wasting good oil but I make multiple short trips per day (less than 10 miles), and I want to follow the B maintenance schedule in my owners manual. I am wondering if the temps I will be seen up here count as extreme. Last year it didn't get above 0 much if at all from about the end of December the the end of February, and during that time it got as low as -20 IIRC. I have been thinking about switching to a synthetic blend for the winter. Such as Rotella T5 in 15w40, or going to a full synthetic such as Valvoline Premium Blue Extreme in 15w40. My concerns with synthetic and synthetic blend are that it will cause problems since the truck has 251,000 miles. Also, I am not sure if it will be cold enough here to make it completely necessary to make the switch. I will be plugging the truck in as much as possible, but I don't think I will be able to during the day at work. I recently read a study done by TDR that indicated that Rotella T is on the low end as far as soot control, while Valvoline Premium Blue is on the high end. I will most likely be switching to the VPB over the Rotella T even if I don't switch to synthetic. You can find the study here https://www.turbodieselregister.com/tdrarticles/tdrarticle56_lubeoilspecs.html.

What are your thoughts?

Been using Valvoline Premium Blue for years. I most definitely recommend using it. I prefer 5-40, as should you in that nasty climate. Just change your filter every 3K, and run the oil until Spring. I change oil twice yearly.

 

[leathermaneod]

Been using Valvoline Premium Blue for years. I most definitely recommend using it. I prefer 5-40, as should you in that nasty climate. Just change your filter every 3K, and run the oil until Spring. I change oil twice yearly.

Which brand was that? You don't think the 5w is too thin during the time between startup and the engine getting up to temp? Also, you would have no reservations about switching to a full syn at 250K?

 

[Freebore]

Which brand was that? You don't think the 5w is too thin during the time between startup and the engine getting up to temp? Also, you would have no reservations about switching to a full syn at 250K?

The 5W-40 and 15W-40 differ in their cold temperature viscosity which is what you want to be concerned about during startup. The 5W-40 will have less flow resistance at startup than 15W-40, especially in cold climates which is desirable. The 5W fluid will flow to critical engine parts much quicker during cold startups than the 15W. I switched several vehicles to pure synthetic at high mileage (gas and diesel) and could not find any real negatives such as leaky seals, etc. I specifically went to 5W-40 as I was concerned that the 15W-40 conventional fluid was simply too viscous for sub zero starts. I understand the new 6.7 Rams get the 5W-40 synthetic now as factory fill.

 

[leathermaneod]

Thanks for the info! Im just really scared of hurting my engine by going to a lighter weight oil especially at such high milage. Ive seen the comparisons between 5w40 syn and 15w40 conventional on youtube and the difference is undeniable. I just can't wrap my head around why, if its safe, dodge/cummins didn't recommend 5w40 in the owners manual. they recommend 10w30 and 5w30, why in the world not 5w40??

 

[RonaldLarson]

Thanks for the info! Im just really scared of hurting my engine by going to a lighter weight oil especially at such high milage. Ive seen the comparisons between 5w40 syn and 15w40 conventional on youtube and the difference is undeniable. I just can't wrap my head around why, if its safe, dodge/cummins didn't recommend 5w40 in the owners manual. they recommend 10w30 and 5w30, why in the world not 5w40??

The recommended viscosity is 10-40 rated for diesel service. Your mileage is far from even being considered for switching to synthetic. Beside the above mentioned flow improvement in 5-40, the superior lube qualities of syn negate any concern for the switch. You have cared well for your engine, you should have zero concern for seals or any other wear items. A zillion long haul truckers almost exclusively use synthetic. They do oil contaminant checks periodically just for the extreme mileage that thy accumulate. Valvoline Blue is the preferred oil of choice at most Cummins shops, as well. Your engine is near bullet proof, don't fear any damage by going to better lubrication. It ain't gonna happen.

 

[leathermaneod]

would you feel safe running 5w40 syn year round then? and what brand would you use? I have heard some not so great things about Rotella T6. Mainly that is overpriced for the fact that it is supposedly not a true syn?

 

[JMcCoy]

Don't let the 5w-40 scare you. The 5 is the cold flow number. It flows like straight 5 weight at a colder temperature. Once up to temp, it flows like straight 40. The oil does not get thicker as it heats up. It gets thinner as it heats up. So when cold, the oil is still thicker than when it heats up. It's just thinner than 15-40 when cold. The oil viscosity is less effected by temperature. That's a good thing.

 

[SAndreasen]

i run shell t6 according to shell its full synthetic the tdr article states he thought it was at least a ;part synthetic but remember the guy doing the test did not know what oils he was testing buy name .we have temps from 100 above to 40 below

 

[Shadrach]

I run Valvoline Premium Blue 5W40 in my 08 all year round, and it gets a lot colder up here. It has had that since day one when my friend bought it new. David