Common

Should I in the winter?

Do any of you switch up?

EDIT: noticed its synthetic - should I even bother?

Or go to 10w 30?

Tate

I run 5w40 year round, helps a lot in the winter.

Doj Dewd

same here. no problems. sure makes a huge difference in the winter on cold start-ups.

oldblues

hi
5 w 40 all year here !

wcbcruzer

I would do 5w-40 all year but I've got some Delvac left so I'm going to switch it up in the summer and use synthetic in the winter.

sjester

FWIW I had a strange experience when I tried to switch to to 5w-40 synthetic Rotella after 200,000 miles of Delvac and RotellaT. I started to get an extreme amount of blowby, to the point that the dipstick would start popping out and, when I replaced the O-ring on the dipstick, I blew over a gallon of oil out the blowby in several hundred miles. Coated the entire tailgate in an oil film on a trip from central Texas to western Wyoming. Went back to RotellaT in mid-trip and had no further blowby issues. Never happened again and ran dino oil until I sold the truck. I searched on the board at the time and didn't find any similar reports. It sure spun nice when it was cold however.

Dartmouth 12V

You should not have any problems just doing the change. There will be a little oil residue left in your engine but not enough to make a huge difference.

infidel

Interesting.
I've found myself and heard others say that that cheaper one cylinder motors will use a lot more oil if it's synthetic. Ring to cylinder fit isn't as good on the cheapos.
Makes me wonder if your engine was wearing out.

John Faughn

Some yrs ago at a bar restaurant , a group sat next to me for lunch , got to talking and they were from a oil lab testing place , got into a long discussion about a lot of stuff , got onto this question , and the gist of what they said was , that the 5wt oils were started by the car/truck manufactures to help pass the millage laws that had just come around near that time .
That non of them would ever use any 5wt oils , because it would compromise the lube of the engine , they were of the opinion that to never use less than a 10wt .
Being here in MN. with temps sometimes as low as -35*F and colder , today when I woke up , it was -24*F .
I used in the past Rottella 15/40wt , now using Amsoil 15/40wt HD marine .
I have forgotten to plug in more than a few times at as low as -25*F , I have noticed very little slowing of RPMs while starting , with either oils .
So I would say that if you keep your starter , contacts , batteries ect. up on regular maintainance , it is best for the longevity of your engine to go to at least a 10wt .

Shagginwagon

I went from dino oil to Amsoil 5W-30 synthetic at my first oil change. Just drained and re-filled. I'm thinking of switching to Amsoil 10W-40 synthetic on the next change, but I will only be draining and re-filling.

sjester

Maybe so, it was just so weird. I literally had to spend $5 at the carwash getting all the oil off the tailgate and toppper I would have a quarter size drop of blowby drip after a couple of days parked before the synthetic experiment and the same amount after I went back to dino oil. Never did actually burn any oil in between changes, before or after, performance never changed. I do know that when I saw the oil over the back and couldn't get oil to show on the dipstick, I needed a change of underwear to go along with the gallon of oil.