dieseldoc Posted December 13, 2012 Share Posted December 13, 2012 I am looking for thoughts on switching to synthetic 5-40 in the winter and back to 15-40 conventional in the summer. You always hear how switching back and forth in types of oils especially synthetic to conventional can lead to oil consumption and leak issues Looking for some opinions on this theory. It has started to get colder here and my 6.0 is starting to run a bit rough in the morning when cold. I usually switch to 10-30 in the winter. However I am running into more situations where I cant always plug the truck in. My thought was to try the 5-40 synthetic to see if it really helps with starting in the cold. The truck has 66,000 mi on it and have run ford 15-40 and 10-30. It typically gets below zero for a month or two here. I also am not a believer in extending oil change intervals with synthetic, just looking fore easier starts at -20 F when I cant plug it in. thnaks for the thoughts guys Quote Link to comment Share on other sites More sharing options...
Matt Saunoras Posted December 13, 2012 Share Posted December 13, 2012 I run motorcraft 5w-40 all year long, 4000 mile oil changes. I think it makes noticable difference especially when it gets cold out. I'm at 87k and 35k has been on synthetic, I've got slight stiction but not enough to cause a miss, just the typical sluggishness from old injectors. I'll be 100% honest, I know we don't go for snake oil around here but I have this in my oil right now. http://www.evergreenamerica.com/index.cf...gine-treatment/ It does make a difference. I would never recommend it to a customer for the obvious liability reasons (not a magic cure all) but it helps the truck significantly before the engine is warmed up. Quote Link to comment Share on other sites More sharing options...
Buddy_M Posted December 13, 2012 Share Posted December 13, 2012 In my two 7.3 trucks over on the other side of the state from you I have been running the Rotella 15W-40 until around late November when it gets it's fall oil change to the Rotella T6 5W-40 Synthetic. I've never noted any more oil consumption than it had before, and it still has the same oil leak at the dipstick adapter it's had for the past 4 years(enough to make it wet, but not leave a drop.) I just started carrying 55gal drums 15W40 in a synthetic blend in my shop, and will be trying that in my trucks next. Have used it in a few customers vehicles so far from the 7.3 thru 6.4's and a few Cummins 5.9s as well and especially notice better running when first started cold on the HEUI engines. Quote Link to comment Share on other sites More sharing options...
Aaron Posted December 13, 2012 Share Posted December 13, 2012 10w30 all year in my 6.4. Conventional. Changed every 3k religiously. Quote Link to comment Share on other sites More sharing options...
Alex Bruene Posted December 13, 2012 Share Posted December 13, 2012 I run 5W40 in the spring, summer and fall months, and 0W30 in the winter months-I park at a carpool lot every other week which is in a wide open space with no protection from the wind, and have no plug in option. I don't switch between conventional and synthetic. Why do you want to switch back and forth? Is it to save a few bucks? Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted December 13, 2012 Share Posted December 13, 2012 What does Bill Hewett recommend? Quote Link to comment Share on other sites More sharing options...
Alex Bruene Posted December 13, 2012 Share Posted December 13, 2012 What does Bill Hewett recommend? I'll ask him next time I go for a shit. Quote Link to comment Share on other sites More sharing options...
YukonTyler Posted December 13, 2012 Share Posted December 13, 2012 Our store is usually Motorcraft 10W-30 in the warmer half of the year and Delvac 5W-40 during the brisk part. We do not have any odd issues with consumption. I use the Delvac year round in my 6.4 .... we pay somewhere around $23/jug. It's not enough of a price savings for me to warrant switching between the synthetic and the Motorcraft seasonally. 6000 km intervals Quote Link to comment Share on other sites More sharing options...
Fordracer Posted December 14, 2012 Share Posted December 14, 2012 Why do you want to switch back and forth? Is it to save a few bucks? Ford used to say to use 15W40 when temps are above 90 and/or you tow alot and use 10W30 for below 90 degrees and light duty use. This was before they offered the synthetic diesel oil so it might not apply to them. I've ran 5w40 in my 6.0 Excursion for the last two years and it makes a big difference on cold start up and it helps fuel economy. On the next oil change I'm using 0W30 and see what happens. I run 15w40 in my 7.3 crew cab dually all year round but I don't drive it in the winter months, I only tow with it. Quote Link to comment Share on other sites More sharing options...
Alex Bruene Posted December 14, 2012 Share Posted December 14, 2012 Why do you want to switch back and forth? Is it to save a few bucks?Ford used to say to use 15W40 when temps are above 90 and/or you tow alot and use 10W30 for below 90 degrees and light duty use. This was before they offered the synthetic diesel oil so it might not apply to them.I've ran 5w40 in my 6.0 Excursion for the last two years and it makes a big difference on cold start up and it helps fuel economy. On the next oil change I'm using 0W30 and see what happens.I run 15w40 in my 7.3 crew cab dually all year round but I don't drive it in the winter months, I only tow with it. Sorry... I meant why switch back and forth between conventional and synthetic oil... Quote Link to comment Share on other sites More sharing options...
mchan68 Posted December 14, 2012 Share Posted December 14, 2012 10W30 in my 6.0L all year round at 5000 kms. (3000 miles) oil change intervals or every 120 engine hours. Quote Link to comment Share on other sites More sharing options...
dieseldoc Posted December 15, 2012 Author Share Posted December 15, 2012 I am going to try the synthetic 5-40 and see how it likes it. I was using the motorcraft oil because I was getting a deal on it, and did not want any questions if I had a warranty repair. However my parts man is retiring and guessing my discount is not going to continue with the other guys. Anyway I was buying bulk from the shop and was a bit of a pain. Was going to switch to delvac because I have run that in all my other trucks and tractors, however finding delvac in 10-30 is almost impossible unless you want to buy a 250 gallon tote. I have been watching and found that the 5-40 mobil oil is available all over the place, so if some was needed along the road would be easy to find. I have been changing oil every 3000 mi instead of the reccomended 5000 mi interval ford says. I forgot they offer a 5-40 synthetic. I will have to read up on it. If the truck likes the oil I will probably just use it year round, would be easier than switching back and forth every season. thnaks guys Quote Link to comment Share on other sites More sharing options...
lmorris Posted December 18, 2012 Share Posted December 18, 2012 which is in a wide open space with no protection from the wind, Doesn't really apply to this conversation a whole lot, but this statement reminded me of a discussion I got into a few years back about wind chills. It does not affect vehicles, only warm blooded creatures. There has to be a heat source, like your skin, that the wind can wick heat off of. It might cool the rad off faster, but once it reaches ambient air temp, the wind no longer affects it. Just thought I would throw it into the mix. Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted December 22, 2012 Share Posted December 22, 2012 What Leon said about wind chill +1 As far as synthetic oil is concerned... Are we talkin' PAO base stock Or "hydro-cracked" wannabe synthetic oil. Where synthetics shine is with temperature extremes. Yukon Tyler might have a case for synthetic oil as <a carefully selected> synthetic oil will resist viscosity change in extreme cold. Notice that extreme cold only applies until the engine (or gearbox or whatever) begins to warm up. I dabbled with PAO synthetics back in the 90s and could not justify the higher costs.... and if you are about to spout <but I can extend my service interval>, you desperately need to realize that it is the add-pack that "wears out" first. Anti-foamants, anti-oxidants, detergents and on and on. If you run your oil until molecular shear becomes a concern, chances are that some component of the add-pack has already expired. I live in an area that gets cold enough to make you zip up your coat... I suddenly realized how stupid that sounds given that I've seen what southerners wear at the Daytona 500. Obviously, I cannot speak for what synthetics can do for extreme high temps - but, if you can plug in your block heater, synthetics for most of us in "cold" climes is a waste of money. Google "Bobistheoilguy". Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted December 22, 2012 Share Posted December 22, 2012 http://www.bobistheoilguy.com ---> Excellent website and forum. Quote Link to comment Share on other sites More sharing options...
DwayneGorniak Posted December 25, 2012 Share Posted December 25, 2012 I have run 15W40 during the summer months in my 7.3L and 0W40 in the winter months ever since I've owned it. Why? Because I tow! Every spring I find that when it is getting warm and I'm working the hell out of the engine it gets a choppy idle due to aeration with 0W40. I switch it to 15W40 for the summer and it idles perfectly smooth. I have always found that 7.3L engines were more affected by aeration than the 6.0L and 6.4L when the oil temp's get high. Call me crazy, but my engine don't like 0W40 in hot weather! Ford used to have a chart in one of the TSB's about the effectiveness of each multi viscosity oil weight and it's thermal breakdown protection based on the weights and the temperatures. referred refered to the 6.0L and "6.4L" engines when I was talking about oil aeration causing rough or choppy idle issues. I think I may have had waaaaay too much Christmas Cheer! There is no way in hell the 6.4L engine would be affected by that being that they are not a HEUI injection system. I'm feeling much better now though! Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.