[HCFL]

Hi everyone, reason I'm writing this post is because of the very cold winter days we've been having in Alberta. I'm talking about -30 to -40 degrees C. I believe I'm hitting the bottom of the low temperature tolerance for the conventional 5W-30 oil in my motor. Every time I start it in dead cold, it's rough... really rough. Almost seems like it's hurting the motor to turn.

I want to switch to a 0W-30 synthetic blend, but I don't want to compromise my engine. I've heard that switching from conventional to synthetic is not a good idea at higher mileage, because of the risk of starting to burn or leak oil. My car goes through 1 quart every 6500 kilometers.

I've heard that using a product like AutoRX is a good idea when switching to synthetic oil.

The alternative is to keep the car plugged in a couple hours before use, but this is not feasible if I'm spending time in a location where I can't plug my car in.

 

[qqzj]

Good luck to you. Since I am going to do it as well, good luck to us both.

But I won't try 0w-30 right away. Try 5w-30 first. It is synthetic, it already flows better. Also I shall use high-mileage full synthetic.

 

[qqzj]

mine is 114k miles, roughly 180k km.

 

[O_loung1]

i have nothing useful to add about cold weather but i can tell after running 1 bottle of AutoRX on my 1mz-fe, my slightly wet rear main seal (a dime sized drop a week) became a gushing fist sized oil spot every half day.

i personally would avoid any synthetics and at the most go with a synthetic blend until you know for sure your under carriage is completely dry if you are concerned about leaks.

 

[speedy25]

High mileage change overs to synthetic is a bad idea. Your engive will oil up everything from leaky seals. If you are prepared to change them before using synthetic you will be OK.

The better solution to your problem would be a new starter/battery/battery cables. One or all three would make your engine start easily.

-SP

 

[71Corolla]

I'd switch to Mobil 1 5w-30 synthetic excellent oil for very low temperatures.

 

[z27ls3]

I use 5/30 conventional

I recently had a 01 camry 4 cyl, It used 5/30 regular oil with no issues. I did not want to chance oil leaks so stayed with specified type and weight oil, I did and still do use BG MOA oil additive available at most new car dealer parts counters, this is the good stuff and really helps on cold starts, also I always have a strong battery. Our temp here in Wy. this morning was -28. High quality oil filters and clean oil in the cold weather will make a difference, I vote no Mobil1 or any full syn, no benefits really in your case.

 

[HCFL]

Battery isn't my issue, the car starts fine but when it does it has to turn over more than normal and it backfires. Seems as if the oil is way too thick to safely start.

So from what I gather from the responses: don't use autorx, and try to avoid switching to synthetic if possible, unless I plan on resealing the engine.

Anyone else with some experience on the subject? I feel as if my motor is in good condition, does that mean much when it come to the switchover?

 

[Kingdom934]

YMMV but I switched my 1985 Camry with about 140K back in 2007 to full synthetic. It was a bit sludge up (black particles) and had a top end knock, so I initially did oil changes every 500 miles with cheap filters. Initially used synthetic blend HM and then full synthetic HM. No bigger or smaller leaks, but again YMMV as the weather in Hawaii is much more stable.

Still been doing the oil changes with full synthetic so far, no issues. Then again, I don't drive the car half as much as before.

 

[71Corolla]

Unless the engine has worn out gaskets and seals there is zero reason not to use synthetic oil. Some myths will never die

 

[speedy25]

Battery isn't my issue, the car starts fine but when it does it has to turn over more than normal and it backfires. Seems as if the oil is way too thick to safely start.

<snip>

I feel as if my motor is in good condition, does that mean much when it come to the switchover?

Hmm, so you admit to hard starting AND backfires but yet you thing your engine is in good condition?

I think not! Good condition and backfire statements dont fit together. You have other problems that need addressed besides what oil to choose.

-SP

 

[Toyota_JP]

"Unless the engine has worn out gaskets and seals there is zero reason not to use synthetic oil. Some myths will never die"

A 1998 Camry with 320,000km certainly doesn't have seals that are in great condition so I agree with others that you do risk oil leaks changing to synthetic. I recently changed the crank and cam seals in my 2000 Solara and they were quite hard and not soft and flexible by any measure. After that many years and that many hours of heat, rubber looses its flexible nature. Synthetic oil has a really high affinity to metal and will literally climb out of the engine through any weak seals. I don't run synthetic in my car but I do use it in my lawnmower and generator. Synthetic oil will climb up the dipstick about 1/4-inch so I always have to remember to pull the dipstick first and wipe off the oil before checking the level. That affinity for metal is great for lubrication but I believe that is why synthetic can crawl through an older seal that is doing an ok job at holding back organic oil.

 

[qqzj]

Crank and cam seals are not a big deal. They can be changed with TB service. The real issue the rear main seal, which is the last thing normal people would want to touch.

But most suggested that they will switch to high mileage synthetic, which will rejuvenate the seals. This might alleviate the concern. The reason I decided to take the risk is because I have seen with my eyes that synthetic does a MUCH better job in cleaning out the gunk and lubricate than dino oil. So I decide to take the risk of rear main seal leaking, in order to better protect the engine.

"Unless the engine has worn out gaskets and seals there is zero reason not to use synthetic oil. Some myths will never die"

A 1998 Camry with 320,000km certainly doesn't have seals that are in great condition so I agree with others that you do risk oil leaks changing to synthetic. I recently changed the crank and cam seals in my 2000 Solara and they were quite hard and not soft and flexible by any measure. After that many years and that many hours of heat, rubber looses its flexible nature. Synthetic oil has a really high affinity to metal and will literally climb out of the engine through any weak seals. I don't run synthetic in my car but I do use it in my lawnmower and generator. Synthetic oil will climb up the dipstick about 1/4-inch so I always have to remember to pull the dipstick first and wipe off the oil before checking the level. That affinity for metal is great for lubrication but I believe that is why synthetic can crawl through an older seal that is doing an ok job at holding back organic oil.

 

[Toyota_JP]

qqzi, agree on the main seal being the big issue. The cam and front crank seals were relatively easy to replace and mine were not leaking badly but certainly had done their time and more. I have the faintest residue of oil showing at the bottom of the flywheel cover so I know my rear main is also leaking some....I'm really amazed it's not a lot worse considering the condition of the front seals I replaced.

You mentioned first-hand experience seeing how synthetic will clean out the gunk. I don't doubt you have....it reminds me of a truck my dad had. You should have seen the wax deposits under the valve cover and who knows what the rest of the engine looked like! I'm not sure what kind of oil he was using, or even if the brand had anything to do with it, but I know he liked Quakerstate and he used to add STP now and then. I think both have a high parafin content...or used to. With that said though, I don't think all dino oil will leave behind residues and gunk. It may just be that the oil formulations are better now but I had the valve cover off my engine to do a cam seal replacement and it was immaculately clean under there. With my experience using Penzoil 10W-30 dino oil in my car, I could hardly justify using synthetic (notwithstanding the original poster's possible need to use a different oil because of his extreme temperature range). However, if my only experience with dino oil had been my dad's truck, I would be totally sold on synthetic.

 

[qqzj]

The first picture is what I see under my valve cover after 13 years. The next one is someone else's car using synthetic oil (can't remember the mileage). There is no comparison. If one wants maximum engine life, synthetic is the way to go.

qqzi, agree on the main seal being the big issue. The cam and front crank seals were relatively easy to replace and mine were not leaking badly but certainly had done their time and more. I have the faintest residue of oil showing at the bottom of the flywheel cover so I know my rear main is also leaking some....I'm really amazed it's not a lot worse considering the condition of the front seals I replaced.

You mentioned first-hand experience seeing how synthetic will clean out the gunk. I don't doubt you have....it reminds me of a truck my dad had. You should have seen the wax deposits under the valve cover and who knows what the rest of the engine looked like! I'm not sure what kind of oil he was using, or even if the brand had anything to do with it, but I know he liked Quakerstate and he used to add STP now and then. I think both have a high parafin content...or used to. With that said though, I don't think all dino oil will leave behind residues and gunk. It may just be that the oil formulations are better now but I had the valve cover off my engine to do a cam seal replacement and it was immaculately clean under there. With my experience using Penzoil 10W-30 dino oil in my car, I could hardly justify using synthetic (notwithstanding the original poster's possible need to use a different oil because of his extreme temperature range). However, if my only experience with dino oil had been my dad's truck, I would be totally sold on synthetic.

 

[mcgowaw]

it'd be nice to know if those engines have the same mileage and years on them, when comparing dino vs. syn oils.
i don't have any experience with full synthetics but i've heard they flow better than dino.
i'm running a syn blend currently but it seems to smoke on startup and give vvti chatter for a second sometimes on cold startups but maybe it will do better with more mileage.
tony

 

[Toyota_JP]

I might agree more with synthetic being better but I suspect the difference between dino and synthetic is minimal in influencing the longevity of the engine when compared to other factors...I'm at 418,000 miles using Penzoil dino. I propose synthetic may be better but why pay for synthetic if I can get 400K miles with dino?

 

[qqzj]

I might agree more with synthetic being better but I suspect the difference between dino and synthetic is minimal in influencing the longevity of the engine when compared to other factors...I'm at 418,000 miles using Penzoil dino. I propose synthetic may be better but why pay for synthetic if I can get 400K miles with dino?

makes sense too. i started changing oil not too long ago myself. so maybe some shops were to blame? If you have the chance to look under your valve cover, please take a picture. curious.

 

[BillySAW951]

Yea I'm planning on switching to Synthetic now at 178k miles on my 1mz 99 v6 I have a leaky gasket I need to swap out its super worn