Just did a transmission fluid and filter change last week
Starting to do my own oil changes next week on my 07 tahoe
Im on the road alot and have 168k mainly highway miles
Is changing to synthetic bad still a myth or should i go ahead and start using 5w30 high mileage synthetic. Shes had regular 5w30 her whole life

Feedback much appreciated!

 

I would definately switch to synthetic, I have 197000 km on my 07 truck and I have been running synthetic since I bought it with 127000 km and it doesnt burn or leak a drop. I also extend my oil changes to every 7000km instead of 5000km running synthetic, and I do alot of pulling with my truck.