ExxonMobil has announced that NASCAR began this month using Mobil 1 Advanced Fuel Economy and Mobil Delvac 1 LE 5W-30 engine oil in its 65-truck fleet as part of the sport’s Race to Green initiative. 

Tony Stewart, driver of the No. 14 Mobil 1 and Bass Pro Shops Chevrolet SS, introduced the the new oils by ceremoniously topping off his a 2014 Chevrolet SS with Mobil 1 on April 4, prior to the start of the Duck Commander 500 Sprint Cup Series race that weekend. 

Michael Lynch, VP of Green Innovation for NASCAR, joined Stewart in topping off one of the NASCAR hauler trucks with Mobil Delvac 1 LE 5W-30. 

 

 

I'm wondering........... who here will try lighter weight oils ?

I remember how hard it was getting people to change from 30/40 weight to 15W40.

Doesnt Cummins not want anything lighter than 30 weight oil used in these engines? If I was planning on living here in ND forever I might think about trying the lighter weight stuff for the winter time. What would the effect be of using the lighter weight oils? Would it cause any difference in pressures? I only ask because I have never run anything but a 40 weight.

I have run Rotella 15 40 since new and never had any oil related issues. With 309k on the clock I would be hard pressed to change the oil I use. Brand maybe, but not the weight.

My thought on lighter oils is a increase in M.P.G.'S

While using 15W40 I;ve seen 27 m.p.g. with 10W30 over 29 M.P.G.

so how high could I get with 5W30 HDEO like Delvac 1 5W30 LE ?

Edited April 29, 201411 yr by skellyman

You have seen those mpg's with a cummins?? If so, that is pretty much record breaking. How did you go about figuring the mileage? GPS?

The mileage was figured by hand ,my 99 does not have a in cab computer.

Previously had a 95 12 v that achieved low to mid 30's mpg.

It had 3.55 gears 5spd manual  the 99 has a automatic and 3.55 gears.

Edited April 29, 201411 yr by skellyman

Wow. Kind of hard to believe that just by changing motor oil weights it would make that much of a difference. I went from a 15w40 Dino to a 5w40 full synthetic and did not notice any difference.

When I take long trips I try to maximize fuel mileage, IE tires aired fresh oil or oilfilter change , lower speed , And no I do not Hyper-Mile for economy.

Wow. That is impressive. I'd be willing to go down in weight of oil myself if I could get a CI-4 or CJ-4 in a lighter weight. The only thing I see here locally is 15w-40 for diesel oils. Being I buy in 5 gallon buckets it make it even tougher.

Hey Skelly can you fill out your sig so we can see what kind of truck and mods you have. It would be cool to compare your rig to my rig in my sig as I also have a 99 24v.

M y truck is bone stock, no mods what so ever.

2wd with automatic.

Well I'm not sure I would want to go to a lighter weight oil with the mods I have. I haven't had the chance to get on the dyno in over a year but i would say that I'm somewhere around 450hp at the wheels... I'm just not sure that lowering the viscosity will help that much in my case but in your case with everything being bone stock 2wd and an auto it may very well work great.

That's what I'm waiting for too is to hear back from http://www.idahoturbodiesels.com/vb/index.php and see when they get a Dyno event going. I want to get some baseline numbers again since my last run was in 2007.

Skellyman -  I find your MPG numbers VERY hard to believe. Were those numbers based off of a whole tank of fuel, or a quick trip up the highway? (down hill with a tail wind)

 

The best I've ever seen a stock truck do is about 21-22 MPG.

 

Question: How does oil weight affect fuel mileage?

The 29 m.p.g. was on a road trip Allen Tx to Mc Alester Okla. common hwy driving.

Lighter weight oils flow more easily .

XOM has done many studies as has Chevron.

Edited May 4, 201410 yr by skellyman

If I recall correctly there was an other member that had 26 or 27 mpg think it had  12v.

You are probably thinking of Moparman. He has made over 27 once but he also has his truck set up to do it. I am still also finding it hard to believe myself. No offense or anything. I have heard people say that they made better mileage with lighter weight oils but it was a to the tune of about .5-1 mpg's better. Even a stock truck I am having a hard time believing. Maybe if it was a 2wd SRW shortbed regular cab with a stick.

I've had lots of people doubt the mileage claims , until they take a trip and see the fill up and the figures 1st hand..... then they're kinda quiet.

  On 5/3/2014 at 10:08 PM, mulcher812 said:

Well I'm not sure I would want to go to a lighter weight oil with the mods I have. I haven't had the chance to get on the dyno in over a year but i would say that I'm somewhere around 450hp at the wheels... I'm just not sure that lowering the viscosity will help that much in my case but in your case with everything being bone stock 2wd and an auto it may very well work great.

Your worry is unfounded , if Delo 5W30 or Delvac 5W30 can meet Cummins ISX M-11 Detroits DD-15 & Mack Volvo standards  why would it not be good in your engine ? All Sae oils are backward compatible , at least until the new PC-11 comes in to use.

  On 5/4/2014 at 10:42 PM, skellyman said:

I've had lots of people doubt the mileage claims , until they take a trip and see the fill up and the figures 1st hand..... then they're kinda quiet.

 

Two forms of verification (ScanGauge II and hand written logs)

 

 

Remember my ScanGauge II numbers are from Home to point A and back home. The fuel logs are from fuel station to fuel statino and might not be the same one. Also my odometer is off by 0.5 MPH so my ScanGauge II is more accurate over my hand math logs.