Moving my 97 Civic over to synthetic. Had a stead diet of dino every 4-5k for the first 148k of its life. Haven't owned it long enough to know if it burns oil. Do I just take the plunge? Start with a HM syn? If I start with a HM am I stuck using it for the future. I grabbed a jug of M1 HM 5W-30 but now I'm second guessing it.
How to transition a high mileage car to synthetic?
- Thread starter zuluplus30
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what oil have you been using?
Dealer bulk 5w-30 since 30k every 4-5k according to the last owner.
Some guys do a 50-50 mix with dino for 2 OCI's then switch. Me...I just dump the syn in there and call it good.
Nick1994
$100 site donor 2024
My car has had dino it's whole life up until 188k and I dumped in synthetic. It hasn't blown up yet
If the previous owner was telling the truth the engine should be very clean. Mobil 1 HM 5w30 is a great oil, i use it regularly. Jump straight in!
I'd probably just keep using dino oil at that mileage!
Originally Posted By: zuluplus30
Moving my 97 Civic over to synthetic. Had a stead diet of dino every 4-5k for the first 148k of its life. Haven't owned it long enough to know if it burns oil. Do I just take the plunge? Start with a HM syn? If I start with a HM am I stuck using it for the future. I grabbed a jug of M1 HM 5W-30 but now I'm second guessing it.
Safest route is to wait until you KNOW the oil consumption BEFORE changing to synthetic...be patient...if the level drops by a quart (F to L/O on the dipstick) or less in about 5k miles then stay with straight (non-HM) syn oil...more than a quart per 5k then go with HM...and stick with 5w-30.
Moving my 97 Civic over to synthetic. Had a stead diet of dino every 4-5k for the first 148k of its life. Haven't owned it long enough to know if it burns oil. Do I just take the plunge? Start with a HM syn? If I start with a HM am I stuck using it for the future. I grabbed a jug of M1 HM 5W-30 but now I'm second guessing it.
Safest route is to wait until you KNOW the oil consumption BEFORE changing to synthetic...be patient...if the level drops by a quart (F to L/O on the dipstick) or less in about 5k miles then stay with straight (non-HM) syn oil...more than a quart per 5k then go with HM...and stick with 5w-30.
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Originally Posted By: Chris B.
Not to hijack this thread but my 1997 GMC Sierra 5.7 Vortec has 83,000 total miles on it and used dino(Castrol GTX 5w30) most of it's life. What Synthetic would be a good choice for it? Thanks
.
Pennzoil Platinum pure plus
Not to hijack this thread but my 1997 GMC Sierra 5.7 Vortec has 83,000 total miles on it and used dino(Castrol GTX 5w30) most of it's life. What Synthetic would be a good choice for it? Thanks
.
Pennzoil Platinum pure plus
You could always go with a gentle synthetic like Mag1/SuperTech.
GF-5 has improved cleanliness requirements, don't know how much a "synthetic" (which may not even be a synthetic) would help, though =most Manufacturers advertise their syns show less piston and cover deposits than their "conventionals".
Know that there exist no "conventional" PCMO in ILSAC land anymore - so the cost/benefit gap is getting smaller with each new certification.
Know that there exist no "conventional" PCMO in ILSAC land anymore - so the cost/benefit gap is getting smaller with each new certification.
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Before switching to synthetic in my Acura, I used Auto-RX. It probably wasn't necessary, but I figured it wouldn't hurt. It had a few leaking seals when I got it, but I replaced them. There was no leaks after switching to synthetic. Now at 210k, it's leaking from the oil pan a bit, but that's probably to be expected from a nearly 20 year old car. It's also leaking somewhere from the top, either the distributor o-ring, valve cover gasket, or cam plug (again). It doesn't seem bad enough to worry about yet.
Originally Posted By: KitaCam
Originally Posted By: zuluplus30
Moving my 97 Civic over to synthetic. Had a stead diet of dino every 4-5k for the first 148k of its life. Haven't owned it long enough to know if it burns oil. Do I just take the plunge? Start with a HM syn? If I start with a HM am I stuck using it for the future. I grabbed a jug of M1 HM 5W-30 but now I'm second guessing it.
Safest route is to wait until you KNOW the oil consumption BEFORE changing to synthetic...be patient...if the level drops by a quart (F to L/O on the dipstick) or less in about 5k miles then stay with straight (non-HM) syn oil...more than a quart per 5k then go with HM...and stick with 5w-30.
I agree here.
Find whatever conventional is on sale and run the same interval the previous owner ran and monitor consumption.
If there isn't any then pick whatever synthetic has the nicest bottle and run it.
Find some used oil analysis of your specific engine here,or ask dnewton if he's got any,so you can get an idea of how long to run a synthetic oil. Typically for a vehicle with a 50/50 mix of city/highway driving you can run 10000 miles but that will get shorter with a higher ratio of city miles,so keep that in mind.
Or just stick with conventional. If it's gone this far with no problems and no leaks why potentially expose a issue where none presently exists.
Originally Posted By: zuluplus30
Moving my 97 Civic over to synthetic. Had a stead diet of dino every 4-5k for the first 148k of its life. Haven't owned it long enough to know if it burns oil. Do I just take the plunge? Start with a HM syn? If I start with a HM am I stuck using it for the future. I grabbed a jug of M1 HM 5W-30 but now I'm second guessing it.
Safest route is to wait until you KNOW the oil consumption BEFORE changing to synthetic...be patient...if the level drops by a quart (F to L/O on the dipstick) or less in about 5k miles then stay with straight (non-HM) syn oil...more than a quart per 5k then go with HM...and stick with 5w-30.
I agree here.
Find whatever conventional is on sale and run the same interval the previous owner ran and monitor consumption.
If there isn't any then pick whatever synthetic has the nicest bottle and run it.
Find some used oil analysis of your specific engine here,or ask dnewton if he's got any,so you can get an idea of how long to run a synthetic oil. Typically for a vehicle with a 50/50 mix of city/highway driving you can run 10000 miles but that will get shorter with a higher ratio of city miles,so keep that in mind.
Or just stick with conventional. If it's gone this far with no problems and no leaks why potentially expose a issue where none presently exists.
Merkava_4 said:
Originally Posted By: Scotty59
Drain old oil, replace old filter with new filter, refile sump with synthetic oil. Done. Really its that simple, have done it numerous times......
Sounds about right to me. With most "synthetics" you are just using a better dino anyway, very few true synthetics on the market anymore.
The group III and III+ synthetics offer similar performance at a better price.
Drain old oil, replace old filter with new filter, refile sump with synthetic oil. Done. Really its that simple, have done it numerous times......
Sounds about right to me. With most "synthetics" you are just using a better dino anyway, very few true synthetics on the market anymore.
The group III and III+ synthetics offer similar performance at a better price.
Originally Posted By: ThirdeYe
Before switching to synthetic in my Acura, I used Auto-RX. It probably wasn't necessary, but I figured it wouldn't hurt. It had a few leaking seals when I got it, but I replaced them. There was no leaks after switching to synthetic. Now at 210k, it's leaking from the oil pan a bit, but that's probably to be expected from a nearly 20 year old car. It's also leaking somewhere from the top, either the distributor o-ring, valve cover gasket, or cam plug (again). It doesn't seem bad enough to worry about yet.
I apparently wasn't awake when I wrote this. It should be "There were no leaks after switching to synthetic."
I also forgot to mention that the previous owner had the oil/filter changed at an Acura dealership every 6 months or 5,000 miles with conventional since it was new in 1994. I think I remember the receipts stating that the first few changes were done around 3,000 instead of 5,000, but I don't have the receipts by me to double-check right now. I bought it with around 120,000 miles on it. I'm not sure what the dealership used, but I think I remembered seeing Valvoline on the receipts. I pulled the valve cover shortly after I got it and it was very clean with almost no varnish.
Before switching to synthetic in my Acura, I used Auto-RX. It probably wasn't necessary, but I figured it wouldn't hurt. It had a few leaking seals when I got it, but I replaced them. There was no leaks after switching to synthetic. Now at 210k, it's leaking from the oil pan a bit, but that's probably to be expected from a nearly 20 year old car. It's also leaking somewhere from the top, either the distributor o-ring, valve cover gasket, or cam plug (again). It doesn't seem bad enough to worry about yet.
I apparently wasn't awake when I wrote this. It should be "There were no leaks after switching to synthetic."
I also forgot to mention that the previous owner had the oil/filter changed at an Acura dealership every 6 months or 5,000 miles with conventional since it was new in 1994. I think I remember the receipts stating that the first few changes were done around 3,000 instead of 5,000, but I don't have the receipts by me to double-check right now. I bought it with around 120,000 miles on it. I'm not sure what the dealership used, but I think I remembered seeing Valvoline on the receipts. I pulled the valve cover shortly after I got it and it was very clean with almost no varnish.
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