I did an oil change in my 96 K2500 Chevy with the 6.5 diesel a few weeks ago. I had some Redline 20w-50 sitting around so I decided to put that in it. Up until then I had been using Rotella T synthetic 5w-40. Do you think that swithching between these two oils could cause a significant decrease in mileage? Thanks.
Losing mileage with 20w-50
- Thread starter BoostedBird
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How much of a drop ??
I havent tested the actual mileage, but the gauge goes down much faster. Sorry I didn't post this in the truck section BTW
20w50 could lower your gas mileage over 5w40 but how much i don't know
I remember reading on the Redline site that they did not recommend 20W-50 if your oil temps were below 225 degrees.
You are brave to run 20W-50 up there in Michigan, especially since it is getting colder and winter is right around the corner, let us know your mileage numbers.
You are brave to run 20W-50 up there in Michigan, especially since it is getting colder and winter is right around the corner, let us know your mileage numbers.
20-50 syn is thick stuff indeed! I like the accurate mileage record keeping though ...
Is this 20w50 a diesel rated oil?
its probably fall/winter lowering your mileage
in MI those cold mornings makes it take more fuel to warm up.. the diff/transmission oil is thicker etc.
I've lost about 5-8% of my gas mileage vs sept. here in NE ohio already. The shorter the trips the more gas mileage will go down because the drivetrain/engine has to heat up some to get the best efficiency
redline has one of the highest hths numbers but its also very heavily friction modified I doubt you would lose a noticeable amount of gas mileage from it vs RTS 5w-40
in MI those cold mornings makes it take more fuel to warm up.. the diff/transmission oil is thicker etc.
I've lost about 5-8% of my gas mileage vs sept. here in NE ohio already. The shorter the trips the more gas mileage will go down because the drivetrain/engine has to heat up some to get the best efficiency
redline has one of the highest hths numbers but its also very heavily friction modified I doubt you would lose a noticeable amount of gas mileage from it vs RTS 5w-40
Another factor to consider is the switch from summer fuel to winter fuel. Winter fuel contains less energy, and you get lower fuel mileage.
Originally Posted By: c3po
I remember reading on the Redline site that they did not recommend 20W-50 if your oil temps were below 225 degrees.
You are brave to run 20W-50 up there in Michigan, especially since it is getting colder and winter is right around the corner, let us know your mileage numbers.
pour point is something like -45C .. not a problem with redline 20w50 in the winter.. hths is a stout 6.1 and its CF rated for diesel.
the CCS number is 50@-15 but thats because the temp they test at changes for each weight of oil.
source = redline site
http://www.redlineoil.com/content/files/tech/Motor Oil Product Data.pdf
I remember reading on the Redline site that they did not recommend 20W-50 if your oil temps were below 225 degrees.
You are brave to run 20W-50 up there in Michigan, especially since it is getting colder and winter is right around the corner, let us know your mileage numbers.
pour point is something like -45C .. not a problem with redline 20w50 in the winter.. hths is a stout 6.1 and its CF rated for diesel.
the CCS number is 50@-15 but thats because the temp they test at changes for each weight of oil.
source = redline site
http://www.redlineoil.com/content/files/tech/Motor Oil Product Data.pdf
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Could have used that stuff as an "additive".
Originally Posted By: BoostedBird
I did an oil change in my 96 K2500 Chevy with the 6.5 diesel a few weeks ago. I had some Redline 20w-50 sitting around so I decided to put that in it. Up until then I had been using Rotella T synthetic 5w-40. Do you think that swithching between these two oils could cause a significant decrease in mileage? Thanks.
Drain the 20w50 but do not throw it away. Pour it back in next summer and run 5w40 during the winter months. You should not need to change the filter.
I did an oil change in my 96 K2500 Chevy with the 6.5 diesel a few weeks ago. I had some Redline 20w-50 sitting around so I decided to put that in it. Up until then I had been using Rotella T synthetic 5w-40. Do you think that swithching between these two oils could cause a significant decrease in mileage? Thanks.
Drain the 20w50 but do not throw it away. Pour it back in next summer and run 5w40 during the winter months. You should not need to change the filter.
You most likely got a dose of winter blend. Here in Wisconsin we start getting winter blend around Nov.1. and I see my mileage drop about 1mpg or 5%. You are also loosing some mpg with thicker oil. I gained 1% when going to synthetics. you may loose 1% going to such thick oil especially going into winter.
I agree with the [censored] Wi winter blend. You loose 1-2 MPG. The 20W/50 will cost you about the same in MPG if you go from a 5W/30. 5W40, i would guess 1 mpg because of the heavy startup weight.
Originally Posted By: webfors
Originally Posted By: Audi Junkie
Could have used that stuff as an "additive".
+1
Perfect top off oil!
+2 I'm not a fan of a 20W50 oil unless there is an oil burning problem. If I was considering using it, the summer would have been a better season. Or as mentioned if I was looking to use it up, I would use it for top up oil. Or 1 qt of it in a 5 qt sump. JMO
Originally Posted By: Audi Junkie
Could have used that stuff as an "additive".
+1
Perfect top off oil!
+2 I'm not a fan of a 20W50 oil unless there is an oil burning problem. If I was considering using it, the summer would have been a better season. Or as mentioned if I was looking to use it up, I would use it for top up oil. Or 1 qt of it in a 5 qt sump. JMO
Originally Posted By: Chris142
Is this 20w50 a diesel rated oil?
This is a good question. The CF rating is not enough in my opinion. The 6.5L GM diesel required at a minimum the following specs.
1996-00, CG-4 or CH-4 required.
It also recommended 15W-40 and in extreme cold 10W-30. Personally I would not run Red Line 20W-50 in a diesel engine.
Is this 20w50 a diesel rated oil?
This is a good question. The CF rating is not enough in my opinion. The 6.5L GM diesel required at a minimum the following specs.
1996-00, CG-4 or CH-4 required.
It also recommended 15W-40 and in extreme cold 10W-30. Personally I would not run Red Line 20W-50 in a diesel engine.
Wouldn't expect a huge variance.
Going from straight 30 to 25W-70 mid winter dropped my mileage (2L J-Car) by 10%, but that was an extreme experiment. 15W-40 to 20W50 syn would IMO be far less a change.
I'd follow Johnny's advice on ratings 'though.
Going from straight 30 to 25W-70 mid winter dropped my mileage (2L J-Car) by 10%, but that was an extreme experiment. 15W-40 to 20W50 syn would IMO be far less a change.
I'd follow Johnny's advice on ratings 'though.
Originally Posted By: Johnny
Originally Posted By: Chris142
Is this 20w50 a diesel rated oil?
This is a good question. The CF rating is not enough in my opinion. The 6.5L GM diesel required at a minimum the following specs.
1996-00, CG-4 or CH-4 required.
It also recommended 15W-40 and in extreme cold 10W-30. Personally I would not run Red Line 20W-50 in a diesel engine.
Ironic thread, I am just asking about CF rated oils for my 6.2 diesel. I agree that the 20w50 is too thick and if its getting cold out, you could do some turbo/engine damage.
These are the specs of the oil I am curious about.
API sm/cf
Acea A3/B3
BMW LL98
Mercedes 229.1
Ford WSS M2C931-B
VW/Audi 502.00 and 505.00.
Originally Posted By: Chris142
Is this 20w50 a diesel rated oil?
This is a good question. The CF rating is not enough in my opinion. The 6.5L GM diesel required at a minimum the following specs.
1996-00, CG-4 or CH-4 required.
It also recommended 15W-40 and in extreme cold 10W-30. Personally I would not run Red Line 20W-50 in a diesel engine.
Ironic thread, I am just asking about CF rated oils for my 6.2 diesel. I agree that the 20w50 is too thick and if its getting cold out, you could do some turbo/engine damage.
These are the specs of the oil I am curious about.
API sm/cf
Acea A3/B3
BMW LL98
Mercedes 229.1
Ford WSS M2C931-B
VW/Audi 502.00 and 505.00.
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LOL 20w50 is for racing engines not 6.2L diesel 15w40 would help
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