Ford Man 14821

Does anyone out there know if there are any dangers or side effects when switching from a conventional oil to a synthetic oil? Can you just go from conventional directly to synthetic with no ill effects? What about switching to a synthetic blend?

Im asking cuz i have conventional Motorcraft 5-20 and would like to switch to synthetic because I hear good things. I just want to make sure that there wont be any gumming or reaction between the two.

whitecrystal1

Motorcraft 5-20 is a synthetic but you can switch to a full synthetic at anytime. The only side effect is if you have a potential for an oil leak going to from dino oil to synthetic will more than likely make it show. All you need to do it switch back. I have read a couple post that some that have switched said there truck started to consume oil with full synthetic and after switching back to Motorcraft it stopped. I switched my Bonneville over to Mobile One around 130K I'm at 207,500 now with no problems. My 02 F150 got switched around the first oil change when Mobile One first came out with the 0w-20 weight, later they came out with the 5w-20 and I stared using it, no problems with it in that truck 56K. When my prepaid service runs out with my dealer I'll be switching this one over and start changing my oil every 5K instead of ever 3K.

jonpan

Switching to synthetic oil is fine .But be sure The oil is the same viscosity as your original oil, specialy if you have a 5.4 3 valve if you switch viscosity the variable cam timing solinoid will not work properly they work off of oil press.& you should not switch back after the change !!

whitecrystal1

Why can't you switch back?? I know you can't switch back if you use High Mileage oil, but no where have I read anything about this for Synthetic.

45auto

Typically, if you have a leak, it's usually on the higher mile engines, when switching over. On the other hand, today's Dino's are far superior than a few years back. This is always a hot topic on diesel sights. If you go Syn, I suggest an extended drain interval. When I do this new F150 of mine, it will be a good Syn. with drain intervals of 10K miles and filter changes at 5K mi. As soon as I run out of the 4 cases of Mobil Dino for my Cummins, I will do as stated above. I'm a freak on oil changes, I used to do them every 3K mi. Now I do them at 5k intervals, just because the oils today are superior in their additive pkgs.. Believe me, I had anxieties on that change over!!

F-l6

Do an engine flush first to rid the engine of old deposits then switch to synthetic.

NGM

OK Here is my .02. I fully endorse the use of synthetics. I DO NOT!!!! EVER Recommend extended drain intervals. Change your oil Every 5 k with synthetics and 3 k with regular oil. I can't count the number of engines I have replaced or that needed to be replaced due to synthetic oil extended oil changes. I need to scan in the pics I have of a customers car that INSISTED on chnager their oil every 15 k because her husband told her that is what the oil could go. She used a high quality synthetic oil. I will not mention the name to keep that argument down. She came in with a valve cover leak and guess what. The head is so sludged up that you can't even see one of the cams and the other cam is barely visable. Why would anyone risk their second most expensive investment over a few 50 dollar oil chnages?? I think its stupid. I don't make a penny more if you change your oil every 5 k or 50k. I just want ya'lls vehicles to last as long as possible. Something to think about if it costs you 50.00 every 5k thats only 2000 dollars in 200k miles. Thats cheaper than a new engine anyday.

F-torque

www.auto-rx.com is a great cleaner for a transition into using synthetics. This is a highly regarded cleaner on www.bobistheoilguy.com

45auto

Absolutely NOTHING wrong with extended drain intervals! To go 10K miles is nothing on today's Syn oils, but change the filter every 5K and top off with fresh oil. I know many people who do this with motors that cost more than twice that of these engines. If anyone is concerned with this practice, you should have an oil analysis to ease your mind. In fact, I know some who only change oil when their oil analysis tell's them to!

If your switching to a Syn at the first oil change, there is nothing you need to do!!!!

Syn WILL NOT sludge your motor! Period! That issue is likely from neglect and other issues prior to any Syn being introduced into the system. If it was a high mileage motor prior to the introduction, along with neglect and lack of maintenance, then likely issues will result.

Education, education, education.

NGM

You are WRONG!!!!!! Any oil will sludge up an engine if not changed properly. We see them come in the shop ALL the time because the engine is sludged up. These cars require synthetic from the factory. Mercedes says Mobil 1, BMW uses Castroil and VW uses Castroil. Mercedes oil changes are 10k oil changes VW switched from 10k to 5k because of sludge and bmw has a 12k oil change interval. We are seeing ALOT sludge issues with the ones that do the oil changes every 10 k or more. I have something better than education. Its called real life.