just bought a new 2006 quad dually diesel ram , and was wondering if its safe to use synthetic oil right away or wait for a break in period? manual doesnt say

 

Most say 20 to 25k mi. for rings to set right & break in. Someone else can prolly tell you more.

 

well, you could put syn in on the first change, but depending on how you break in your engine, that could be a little too early. i switched over to synthetics at 12,000 kilometers iirc [~7,500 miles] and no issues with me

 

I would put at LEAST 10,000 miles on it. I have always waited then switched over to Amsoil.

 

Some have posted swapped over at 3k etc.with no issues.I waited until 15k.

 

I changed out mine at 3000 but I did change mine out once before at 1500 with rotella get the break in oil out no problems. Red Line 15-40

 

Cummins will say wait till 15 to 20k.I think its listed on their web page under questions and answers but as I stated others have done it much earlier.