Redline 15W-40: interesting results

[Hohn]

NO oil wars, please, just here to report some interesting findings after recently switching to Redline 15W-40 from Delo 400 (also a good oil).



1) Peak boost is up. Before with just the EZ, I could only hit 27psi. Now I have hit over 30 (oil was the only change).

2) Turbo comes down slower when you let off. Instead of the needle diving to zero as soon as you lift, it seems more to coast down now. It's subtle, but noticeable.

3) Cruise boost is about a 1-2psi more at my standard speed of 75MPH. This is from calm days (no headwind).

4) SLIGHT reduction in average EGT-- like 30-50°. I think the marginally higher boost plays a role here.

5) Engine is quieter. Not so much from outside the truck idling, but from the inside cruising down the road you can tell that is runs a little smoother, with a little less clatter. This is only the case when the CTD is at or near operating temp (within the normal band)

6) the turbo spools a little faster.





I can only theorize that the oil has reduced friction in the turbo, allowing it to spool more quickly, maintain a higher speed for a given fuel rate, and spin down more slowly. I hope I also have similar friction reduction in the engine itself.



It makes sense for the above enhancements to happen, since Redline's base stocks are the same as those used in jet engines, and designed for turbines and high speed stuff.



At initial blush, I am very pleased, and as happy with the Redline oil in my CTD as I have been with their other products used elsewhere.



HOHN

 

[RustyJC]

Hohn,



I'm not surprised. I've used Delo 400 15W-40 ever since the first oil change. A few weeks ago I backed the truck out of the garage to do some work on it that involved pulling the BHAF. Well, I reached in just to give the turbo impeller a spin to check everything out and couldn't believe how "stiff" the rotor assembly was. I wasn't about to spin anything with cold oil - 1/2 a revolution was about it!! It certainly has me thinking... ... .



Edit: By the way, subsequent to this check, I've towed the 5th wheel and got 30 PSIG boost at WOT with everything at running temperature, so the turbo itself is OK.



Rusty

 

[John]

Hohn, I'd be interested to see what you receive for oil analysis results after using the Red Line 15W-40 synthetic for awhile.



I used the same oil from 13. 5k mi. on my 24v CTD to about 46k mi. , switching to Amsoil 15W-40 H-D Diesel & Marine.



And no, I'm not an Amsoil junkie, I'm using it because it works well, I received much better oil analysis results and could procure it easier and cheaper (once I became a "dealer"). However, that is not to say I won't ever switch again... maybe to Royal Purple or back to Red Line again... who knows? They may have changed (i. e. , enhanced) the formula of their Diesel oil.



BTW, prior to switching to the Red Line 15W-40, I had been an absolute diehard Red Line fan over over 9 years at that point. I have been strictly a synthetic lubricant user for well over 20 years now.



BTW, no oil wars for me! You all use what you like 'cause I'm gonna do the same and could give a RA what you use and why.



(I'm tired of fightin')

 

[Hohn]

I hear you. I won't say I am "diehard" for Redline. Certainly not to the degree that some folks feel about a certain oil that starts with "AMS". But I have been impressed with their products. I dunno if it's their marketing or what that got me, but maybe I AM a sucker. But this sucker likes the stuff enough to pay $30 a gallon to use it.



I have used their assembly lube, chassis grease, 10W-30, 15W-40, D4 ATF, and their fuel additives. ALL have impressed me (excpe teh price, that is). I have a bunch of Shockproof Heavy on the shelf for my next (and probably last) diff change.



I too would be open to trying something else if it was better and I could afford it.



Hohn

 

[Hohn]

Why more boost?

Someone raised an interesting point to me, so I think this is worth mentioning:

Increasing engine efficiency can sometimes lower boost, sometimes make it higher. It depends on where the improvement is. Boost is directly proportional to fueling. However, the percentage of that fueling that is converted to boost is influenced by the friction in the turbo and how fast the heat is bled off from the exhaust. For example, an aluminum exhaust manifold would produce less boost than the iron one at the same fueling because it looses heat.

Friction in the turbo wastes exhaust energy (from fueling). So when you reduce friction there, a higher percentage of the energy is converted, and you see the higher boost.

Normally, higher boost means the engine is having to work harder. So, you would think that if the engine isn't having to work so hard, then you would have lower boost, true?

At highway speed, the biggest thing the engine has to labor against is wind resistance. Tire rolling resistance and other sources of friction hurt efficiency. Compared to these, the engine's own internal friction is VERY small in contributing to the overall load on the engine. Thus, the decreased friction influences one of the smallest factors that would tend to REDUCE boost, but influences one of the LARGER factors that would tend to INCREASE boost.



That's my thinking anyway. Feel free to explain why I am wrong.



HOHN

 

[illflem]

I was wondering the same thing

Higher boost indicates less mpgs and it's not the increased resistance of the turbo causing it, it's due to more fuel. I would think with synthetic your boost would be lower rather than higher.

 

[Steve Campbell]

Just My observation.....

I ran a PDR 35 for a while and the boost pressure was higher in all applications than the factory 35. Now I realize this was due to the larger impeller on the compressor side. Perhaps a small portion of the "efficiency" gain was from a more "balanced" assembly.



Similarly, the decrease in "drag" that Hohn talks about from the "lubricating medium of choice" would allow the "assembly" to rotate with a smaller percentage of parasitic drag on the mechanism. This dreased "drag" should (IMO) relate to a gain in overall efficiency, which in this case, sounds like increased boost.



again, JMO

 

[RustyJC]

For a given load and a corresponding given level of fueling, there's X amount of exhaust gas horsepower (ghp) available to drive the turbine end of the turbocharger. This horsepower is consumed as, say, 80% turbine efficiency x (compressor hp + frictional loss hp). If X remains constant and frictional loss hp drops, the turbo will speed up until the new compressor hp rises enough to make X once again equal to 80% x (larger compressor hp + smaller frictional hp). Therefore, for a given amount of exhaust drive ghp, reduced frictional losses in the turbocharger will translate to increased boost as increased flow and/or head is required to increase the compressor hp.



Rusty

 

[Hohn]

yeah, what Rusty said^^^^ (why can't I 'splain it so well?)



Hohn

 

[Jetpilot]

I'm betting that you had some oil coking going on with your turbo and the synthetic oil cleaned the residue from it allowing it to spin easier... ... I have seen this before on my truck. Just my $. 02 worth



Doug

 

[Hohn]

Oil coking? With only 10K miles on my truck? All of those where on Rotella (until 3K) then Delo (two changes). If it was coking already, I have a lowered opinion of those fine oils.



BTW-- I always let my truck idle down until EGT cools off (under 350 or so).



I suppose it's still possible, though I have never run my truck that hard (no loads to pull). My turbo doesn't even have a "tan" yet!



Hohn

 

[DocStressor]

Hohn- I agree with JetPilot. You can coke your turbo bearing with ONE hot shut down. The burned oil is usually washed away during the next operation cycle, but deposits can stick to the turbo bearing and cause it to bind. That might be the cause of RustyJC's tight turbo as well. The difference in frictional coefficient between two 40 weight oils is negligible relative to inertial load of the turbo. If "friction" was the only factor, everyone switching to a 30 weight oil would see a significant increase in boost and that just doesn't happen.



Redline oils are notorious for cleaning out deposits and residues left over from previous oils. They use an ester based oil that has rather strong polar properties. What that means in English is that the oil has a high affinity for metal surfaces. Deposits from previous oils contain trapped wear metals. That is why most people who do oil analysis after the initial switch to Redline typically see a spike in wear metal levels that often scares them away from the product. The wear metals (and oxidation) generally drops with continued use of the ester-based oil. Take home message: Don't try an extended drain the first time you use Redline.



Rusty, there is a product out there called AutoRX, which pretty much acts in the same way as polyol esters. It is made from esterified fatty acids (the same stuff you eat) and you just add it to conventional oil for 500-1000 miles prior to a drain It appears to be very safe and effective. It would be interesting to see if it frees up your turbo. Just do a Google search to find out about it.



Does anyone know if Redline DIESEL oils contain moly? Their regular oils are loaded with the stuff. I have some concerns about moly in HD diesel oils (as does Cummins).

 

[fourwhls]

I have yet to switch to Redline in my truck, but will be done very soon.



I only have experience using redline oils in my Racing ATVs. The oil looks like crap but really works.



This picture was taken after the bike was sitting for more than 24hrs. Look how the oil is still sticking to the gears.



I thought it was rather impressive.

 

[fourwhls]

a closer look

 

[RustyJC]

Originally posted by Lee Weber

You can coke your turbo bearing with ONE hot shut down. The burned oil is usually washed away during the next operation cycle, but deposits can stick to the turbo bearing and cause it to bind. That might be the cause of RustyJC's tight turbo as well.



Rusty, there is a product out there called AutoRX, which pretty much acts in the same way as polyol esters. It is made from esterified fatty acids (the same stuff you eat) and you just add it to conventional oil for 500-1000 miles prior to a drain It appears to be very safe and effective. It would be interesting to see if it frees up your turbo.

Lee, I guess I'm like Hohn. I'm absolutely anal retentive about maintenance of this truck - it's at 12,800 miles now, and it's had oil (Delo 400 15W-40) and filter (Fleetguard Stratopore) changes at 2,000, 5000, 8,000 and 11,000 miles, and I never shut it down until pre-turbo temp is below 250 degF for at least 30 seconds or more. I'm really struggling to accept that I have a coked turbo bearing. If I do, then I really can't understand why turbos aren't failing left and right among the "great unwashed" legions of Dodge Cummins owners who aren't members of the TDR.



At any rate, since I'm coming up on an oil change in about 1,200 miles, I'll do some checking on this AutoRX product.



Rusty

 

[Hohn]

Originally posted by RustyJC

Lee, I guess I'm like Hohn...

POOR GUY!!! Pass the collection plate everyone!!



Seriously, though, I can see where you are coming from, Lee. But I don't see how my turbo would be coked at all. I agree with what was said about the absence of turbo problems among non-TDR members.



I also agree, Lee, with what you said about Redline, but I am going to run a little longer on my first Redline drain. This is simply because I believe that 10K miles is not sufficient time or usage to have the kind of engine deposits that would lead to the problems you describe. If I were converting a 50K miles gasser over to Redline, I would wait a few drains before extending. But I only have 10K in a diesel that runs much cooler than most gassers (therefore fewer oil deposits?).



I also know that I wasn't supposed to switch to synthetic this early (10K), but my engine was acting like it was broken in-- sounded really smooth (and different than when new) and also it used almost no oil. I feel comfortable with converting at this point, even if I wouldn't recommend it for everyone. Truth is, it's probably much ado about nothing (you know how bad we TDR guys are about making mountains out of molehills).



I wonder if Keith or Lawrence from DD will chime in and tell us why they recommend Redline on their website.



Lee, I agree with you also that a 30wt should have more boost than a 40wt oil if friction was that great a concern. The turbo sees a lot of viscous friction, so a more viscous oil would only seem to exacerbate this. Why DON'T we see people reporting more boost when they run a 30wt?? How come I DO see more boost? They don't seem to jive. .



BTW-- Seems by boost has dropped off to about 29psi max. I can't break 30. Still an increase over before.



I don't know how to personify it or make it anything other than subjective-- but the engine just seems to really like this oil.



We'll learn more as time passes.





HOHN

 

[DocStressor]

Rusty - The turbos hardly every fail, even with abuse. I wouldn't really worry about it. Actually, I'm feeling kind of guilty about recommending AutoRx (once you see what it costs) just because I'm curious about learning whether it would make a difference for you. How long was your engine sitting idle before you tried to spin the turbo? I've only tried this once myself when I looked to see if there was any oil accumulation from my air filter. The engine hadn't been sitting long and the turbo spun freely. The oil drains off the bearing as the engine sits just like any other part. But the turbo bearing gets the first shot of oil upon startup because of the direct line from the filter. Maybe yours just had some drag because the oil had drained away.

 

[RustyJC]

Originally posted by Lee Weber

How long was your engine sitting idle before you tried to spin the turbo?

No more than one (1) hour. Ambient (and oil) temp was probably 55 degF. It didn't feel "scratchy" like there was physical contact - it just felt like the turbo center section was full of STP!



Rusty

 

[DocStressor]

Ok, you got me.

 

[Pit Bull]

:-laf Oil, lets see big industrial strengh engine in a pickup truck. It's been reported CTD's have lasted over 1,000,000 miles without an over haul on dino Rotella T 15w40 with over 5K mile changes. Now if we were talking about a "high RPM" percision fit 3. 2 liter Acura NSX engine, that regularly goes from 0-60 mph in less then 5 seconds I would say lets figure out what oil will keep this baby going a few extra miles. I will even go along with a need to sample and find a very high performing oil if you race and have a 400+ HP CTD. But for me the Rotella T 15w40 will do . It is interesting hearing what you guys find out about the performance of the different oils so please keep posting your finding. Who knows I might inherit some money and end up with a 400+ HP CTD