Been using 5w 20 semi synthetic every oil change and filter 3500 miles

I am going to make a change to FULL synthetic is there any problem doing so after using synthetic mix or for that matter regular oil?
I will keep same viscosity.

Second question: If changing to full synthetic (got great price on it) can I go 7500 miles? If so do i still change filter every 3500 miles.

Is there established fact to stay with same viscosity and not go thicker same 10/30 as car gets miles (65,000)? Hot summers.

 

I say you're safe to use it, the only thing is that if you have any oil leaks with regular, or semi synthetic, you will have leaks with full synthetic. Honestly from what I was told by hydra shocker, synthetic blends are just a total waste of time.

2nd: You may be able to go 7500 miles on a synthetic oil but I would only go 5-6k. Its your call though. You can buy high grade oil filters that are guaranteed for up to 10k miles, but then its only good for "Up To" 10k. It could be 5k, 6k, 7k, or even 8k. IT depends on the shape of your motor. For the first few changes I would suggest a 5k interval to help clean out your engine better, and then if you really wanted to do a 7500 mile interval then like I said, it's your call.

 

An old problem that has been addressed with additives in synthetic oils. Press on.

Here's an article full of oil info. Your question is addressed in the video "Debunking Common Myths": http://www.edmunds.com/car-care/stop...-your-oil.html

 

06 caravan 3.8: Well what i did get out of the video was:
1) can change to synthetic oil from regular or vice versa
2) Go by owners manual--it says every 3,000 miles and filter at same time--manual didn't distinguish between regular and synthetic intervals--just said 3,000 miles (too bad)

closing remarks: then why buy synthetic if changing every 3,000 miles as directed by manual. Again TOO BAD. That ends up being some bucks. Get cheapest stuff as long as meets the specs.

 

My 07 Ford and 06 Toyota says every 5000. My daughters 06 Honda says every 10,000. The Chrysler 3000 mile requirement seems a bit out of date to say the least. Then again it help keeps Chrysler dealers busy and in the black.

 

No thats because the engines werent designed with synthetic in mind. Using a finer, more durable synthetic oil you can easily go 5k miles on a change. My synthetic I bought has like a 10k mile guarantee on it, as does my filter.

 

"Full synthetic" means what? It could still be from Group 111 base stocks = petroleum oil / dino / whatever.
Blends come from a mixture of group 11 and 111 base stocks.
For a true synthetic (non petroleum) oil go for something made completely from Group 1V base stocks. Castrol 0W-30 European Formula/made in Germany and Amsoil come to mind.
You can go up to 6000 miles on conventional oil, depending on service conditions. I run whatever 10W-30 (5W-20/30 in winter) oil is on sale, an oversize Mopar filter (same size as FL-1A or Fram 8A) with intervals between 4700 (7500 kms) to near 6000 miles (9000 kms). Most newer Chrysler specs say 6,000 miles max regardless of the oil (conventional / want-to-be synthetic / synthetic) used as long as it meets their specs. FWIW, unless you looking at 10,000 - 12000 mile oil change intervals, stick with the less expensive oil and not blends, providing they meet Chrysler specs.