more feedback on 0W40

[srjd]

Ive posted about this before but I was hoping to get more reassuance with the warmer weather approaching. Ive been running mobil1 full syn 0W40 in my truck all winter and ive been changing it every 3500km because I get it for free so I want to keep my motor healthy. My question is does anyone on here run it in the summer in there 6.4? I figure its a 40 so once its up to temp its the same protection as 15w40

[Oilboy]

Yes I have always ran the 0-40 synthetic winter and summer. Never had a issue with temps while pulling even in kelowna at plus 30 Also run the Mobil 1 and before that the xd3 which is the same oil, between myself and my old man we have over 1200000kms on the oil between 5 trucks neither one of us have had 1 motor issue
1 99 7.3 sold at 450k dads
1 07 6.0L sold at350k dads
2 6.4's 08 traded at 200k 2010 at 80k and will be around for a long time. Mine
1 11 6.7 At. 180k dads.
Since you get it free 3500 O/c is nice I run mine to 12000Kms