Wish2345

i bought my 00 civic Si with 145k on it a few months ago and didnt really know the previous history maintenance wise but have always used Mobil 1 in my cars so i changed the oil using 5w30 Mobil 1 and now i seem to have a few leaks here and there. Thinking my oil pan gasket may be bad as well. I am wondering if putting the mobil 1 synthetic oil in has caused all these leaks to start or if i just didnt notice them. I have no idea what kind of oil they used in the 145k miles before i owned the car. With it having some higher miles should i go back to conventional 5w30 or 10w30 oil or is it too late?

kzelisko

synthetic oil is more slippery than conventional oil. It is also better at cleaning. As such gaskets that are now making marginal sealing after years of being on the car, synthetic can slip through where a conventional oil would not. I would just fix the leaks and carry on. They would have leaked eventually anyway.

98civdx

fix all the leaks,
just keep an eye on the oil level, if it starts to burn put normal 5w-30 back into it.

newtron63h

first of all, on a street engine with some mods and bolt-ons.........you dont need synthetic........conventional oil will do everything a street engine needs it to do.

so that being said........conventional oils and synthetics affect the rubber in seals differently. which is fine if you stick to one or the other.......or if you use conventional for a 1000 mile break-in.....but after 10 years of use your seals have gotten used to the additives, detergents and such in conventional oil.....by switching to synthetic you have changed which detergents and additives your seals get........that combined with the above-mentioned fact that synthetic molecules are smaller so can get into smaller spaces...........you now have leaks. only one way to fix it.........replace the seals........pick an oil and stick with it.

but like i said.....unless the factory calls for it, or you have some serious performance mods........synthetic is not doing anything that conventional wont cover.

BryanM.

iTrader: (1)

x2


.

strategy400

Synthetic is better and worth the money no matter what it's run in. I immediately noticed my valve lash stopped opening up after switching which I take as reduced cam wear.

It also cleans better. Could be some dirty oil particles floating around in there interfering with the seals' ability to seal. Try a few more oil changes with the synthetic and see what happens.

newtron63h

93 Si, owned since brand new 165k on it now...........replaced the VC gasket at 155k.......all valves were right in the middle of spec.....never been adjusted. all that engine has seen is castrol gtx 5w-30.

synthetic is a waste of money in engines that have been and continue to go 200k, 300k, 400k, 500k on conventional.

once you get into more serious mods like bigger cams, turbo, increased compression, higher rpms, where there are higher stresses on engine parts is when synthetic has the biggest advantages.

do you have aftermarket cams in yours?

apexi_rsx

synthetic oil can seap through smaller holes then conventional oil will. so after all those miles n wear n tear im sure u need ur seals replaced and u should be fine..instead of 3k miles changes; synthetic oil should be replaced every 2k miles. im still using conventional oil in my turbo d with 120k miles with no problems.

Ruben19

switch back to regular 10w30 oil

newtron63h

thats not correct, synthetic oil can go LONGER between changes.....usually if you did 3000 on conventional then 5000 is ok between changes on synthetic. in fact it has been shown that under non-severe driving(highway cruising only) that synthetics can go with just a filter change every 5k and can go 10-15k on the same oil before oil breakdown gets to an unacceptable level.

unless you have something like a turbo that puts ALOT more heat into the oil(especially if you dont either have a turbo timer, or allow the turbo to cool and spool down before you shut it off) or an issue like rings leaking which contaminates the oil(diesels fall into this category)......5k is fine for synthetic.

Red_Army

idk where your buying your oil but synthetic here is like maybe 2 bucks more for 5 quarts. so its not really a waste of money.

and why is it that euro cars ask for synthetic when they are all stock cars and only a few have turbos that aren't run high either. if synthetic is such a waste.

just wondering. both lube places i've worked made us go through long boring courses on oil. and synthetic is better mildly but it is.

and synthetic is 4-5k not less. then itd be a total rip off.

newtron63h

what i mean by a waste is that when conventional will do everything your engine needs.......then why pay the extra $2 a quart for synthetic.

as far as cars calling for synthetic.....part of it is that they design the engine to run with synthetic(composition of seals, tighter tolerances, etc)...because it is better(car companies dont like honoring warranties) so if they can make the customer pay more for better oil......and in return they dont have to replace as many engines, they are all for it.........the other part of it is called kickbacks, alot of euro cars these days advertise castrol right on the engine, which im sure castrol either pays for OR gives big discounts to those manufacturers.....which is the same thing.

to get a similar effects of cleaning like synthetics do.......add some ATF to your engine oil......maybe a quarter of a quart per oil change.

Red_Army

true.

hah for the month i worked at a dealership. i know how much they love to try and find something to void that warranty to make you pay for it. makes sense saves them money and holds the parts out til just after the warranty expires.

apexi_rsx

i got my oil changed at the stealership and they recomend every 2k. synthetic does not last longer then conventional. its a myth it gets contaminated as much as conventional. many companys advertizing longer oil change intervals ,but have back down from thier statements and recomend u change it every 3-5k still. some motors that have hydralic oil tensioners for timing chains or belts and need clean oil more then others and require to change evry 3k. Saturn S series for example.

newtron63h

the dealership told you to change at 2k? sounds like they thought you were an idiot and are trying to get more gravy money from you.

yes synthetic does last longer, its designed that way, its a more stable lubricant than conventional. there is no myth, synthetic is better than conventional oil in every way except price.

yes it gets contaminated, but thats why there are filters designed for synthetics, since synthetics have smaller molecules.......the filters are designed to filter smaller particles.

strategy400

Lets take your 300,000 mile car.

Say 4 quarts of conventional costs $16

Say 4 quarts of synthetic costs $28

At 5000 mile (synthetic) intervals you change your oil 60 times over the life of the engine.

At 3000 mile (conventional) intervals its 100 times.

Math:

100 X $16 = $1600

60 X $28 = $1680

$80 more for synthetic, factoring in less time and trouble doing oil changes and considering:

Then the answer to:


Is - because its well worth $80 more and less frequent changes over 300,000 miles.

newtron63h

its kinda like cars.......yes a audi R15 is faster than pretty much any street car......but any advantages it has are unless you live at the nurburgring......so why use it as a DD?

using synthetic is fine if its been used since new(or conventional for motor breakin and then switch to synthetic) but its very common to develop leaks if you switch..........so why deal with that when conventional is getting the job done just fine.

300whpej

there's no reason to even think of switching back to conventional oil. synthetic is a better quality oil and will help clean your engine of contaminants. where i live, autozone always runs specials on the mobil 1 oil/filter combo for 18.99 and sometimes i grab two if i know im gonna do a lot a highway miles in the next few weeks so that i have another oil change waiting. ive used synthetic oil in every car ive owned/maintained over the past 5 years with no problems. honda, dodge, lincoln, no issues, and i can go longer between oil changes. ive always heard that once you start using synthetic oil you shouldnt switch back to conventional oil anyhow.

sidenote: why do people always say synthetic oil/premium gas is a waste of money, then go enter their CC#s on pwjdm.com?

infinitypro12

I did quite a bit of research last summer on this and your engine doesn't have eyes, synthetic 5W-30 is the same viscosity as traditional 5W-30. The only real difference is the materials used to manufacture the end product, leaving one highly degradable and one scientifically engineered to decrease break down. All the Synthetic propaganda you see is bullshit. Both will work but if you are lazy like me synthetic is worth it's weight in gold, or cash, ha ha.

newtron63h

how is premium worth the money when the car runs 100% fine on regular....especially in a stock engine......even with some simple bolt-ons.......premium is going to get you almost ZERO gains.

i also dont think synthetic is a waste of money.............i think its a waste of money(and possibly time if you develop leaks) on stock or near stock engines.....unless the factory calls for it.

like ive been saying.........why switch to synthetic when conventional is getting the job done BETTER than your engine needs. every engine oil available meets or EXCEEDS the requirements it has to meet(in pretty much every case it exceeds all if its requirements).........therefore it EXCEEDS the needs of your engine.

so wheres the advantage? longer oil changes? most americans dont have cars long enough for that to really matter.

Wish2345

i know people will have their opinions as to which oil is better and i could have very well had those leaks before i put my Mobil 1 synthetic oil in my car. I just was trying to see if b/c i dont know what type of oil they put in the car before me if going from synthetic to conventional will hurt me. I guess ill just stick with one or the other and not go back and forwth and will fix my leaks and rock on.

newtron63h

good idea.

vanilla_rice

I used castrol edge this summer and developed leaks everywhere from it. I've owned my 96ex since new (newtron63h, there's not many original owners on here) and it's never had a leak EVER and had almost exclusively conventional (<4 synthetic changes and the last was about 50k ago). Kind of funny that at 192k miles, without a single leak previously, that my front main, rear main, and oil pan gasket would start leaking at the same time if it wasn't related to the synthetic. I wouldn't change oil types if you don't want to be replacing gaskets. I wish I hadn't trusted Castrol's marketing.

SHO-NUFF

LOL!!!! That just made the rest of my day!!! I couldn't agree more with you. Hope you don't mind I keep that in my sig from now on.

BlackDeuceCoupe

First of all... I've been running Mobil 1 for years.

Secondly, I'm running a 99 Si motor.

LoL! Thirdly, I solved my leaky motor (75,000 miles when I got it) by using Mobil 1.

Here's the trick...

Mobil 1 (and everyone else) changes the oil formulation from time-to-time. The current (standard) Mobil 1 oil is made for 2005 and newer cars... not our old Si motors.

Here's a long post where I explain the whole situation ad naseum: https://honda-tech.com/forums/showpo...3&postcount=11

Bottomline: You need to run Mobil 1 HM (High Mileage) - not that regular neutered ****.

Your Si motor will last a lot longer, because it has the proper additive package for our motors, plus it comes with anti-leak compounds to stop the leaks.