Switching to synthetic

lucas6.6

New member
Aug 20, 2014
99
0
0
Wisconsin Rapids, WI
I've been thinking about switching to synthetic oil in my truck and I have a couple questions.
Is there anything I need to watch out for when switching? I've heard synthetic can expose worn/old seals and cause leaks.
What kind of service intervals are guys running that use synthetic?
And finally which brand would you guys recommend? Truck has 226k miles, if that makes a difference. I've been looking at either amsoil or schaeffer's.
Thanks
 

NC-smokinlmm

<<<Future tuna killer
May 29, 2011
5,214
364
83
At Da Beach
I'd just stay with dino oil, your gonna spring some leaks if you go over. The seals were never ment for synthetic oil. I did this with my lmm and it instantly had an oil leak on a valve cover that never leaked a drop with conventional oil, plus wayyy more seepage...
 

Cknight199

New member
Aug 23, 2012
1,827
0
0
Salt Lake City, Utah
I had a sludge buildup around my valves when I tore my heads apart. My motor builder said it was due to me changing to synthetic, and advised me to run conventional oil in my new motor.


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LBZ

Super Moderator
Staff member
Jul 2, 2007
9,905
151
63
46
B.C.
Hmmnnn, I was going to run Mobil 5W-40 synthetic in my built engine once I get it done. Maybe not a good idea? Or should be fine if I run it from the start? Winter's are long and cold up here with lots of idle time was my justification for it.
 

PureHybrid

Isuzu Shakes IT
Feb 15, 2012
3,517
501
113
Central OH
10-4, i will be staying with the Mobil delvac I'm running now. As far as conventional oil goes what are some of the higher quality brands?

Your delvac is one of the best. I'd run that or premium blue. We ran the Valvoline premium blue at the Tech Center in EVERY engine unless a certain test specified otherwise. That oil was put through hell. Guys on this site complain about high oil temps, try 280°F for 250hrs :thumb: they call that the "Hot box" :roflmao:

I'm not one to believe that switching oils makes an engine leak and/or burn it. Thing of the past with old style gaskets and valve seals. If you switched and sprung a leak, there was a hidden reason.
 

ty_LBZ

Camaro killa
Dec 6, 2014
297
1
16
Farmington, NM
I'm running Mobil 1 5W-40 with no problems. Been changing it every 7.5k, I start getting worried beyond that point. I maybe dumping out good oil, but I like the peace of mind.
 

OregonDMAX

NOT IN OREGON, NO DURAMAX
Apr 28, 2013
3,964
8
38
36
Goodyear, AZ
I'm running Mobil 1 5W-40 with no problems. Been changing it every 7.5k, I start getting worried beyond that point. I maybe dumping out good oil, but I like the peace of mind.

I change mine 2.5 times in the time you change yours once.