A bad PCV valve or ring blow-by can make the oil black prematurely. If you have been running dino and have sludge buildup, and then switch to synth (especially lighter weights) the syn will break down the sludge (effectively cleaning out your motor) and will come out black until the engine is clean inside. Thats why syn can cause some seals to leak- the sludge was hiding a bad seal.

 

I've always run Mobile 1 in everything. In my RX7 I noticed a slight temp. drop when I started using synthetic and the turbos seem to spool faster and quieter?? THe RX's rotory motor is very sensitive to heat so anything to cool it down helps. I also track it from time to time where synth's resistance to breaking down in high heat conditions gives me added comfort.I get a small improvement in fuel mileage as well. The 4Runner seems to like the synth better too.

 

Here's a oil filter comparison

http://minimopar.knizefamily.net/oilfilterstudy.html

I use the Mobile 1 M1 or Puralator PureOne filters myself.

 

I've used Mobil 1 in my vehicles because of a fellow gearhead on another board (who happened to be into the oil analysis and research facility) did a bunch of sampling testing of various oils.

A lot of the testing was done on motorcycle oils, or oils that were popular for use in motorcycles.

Mobil 1 was ONE of the consistent leaders in resisting contamination, and providing great protection.

Some other site gave a list of synthetics which actually improved power (there were a few amongst the many) and Mobil 1 was one of them.

It is certainly not the ONLY good synthetic out there, but it happens to be my choice most of the time.

 

I've been running M1 for about 3 years in the 3.4s listed below. I change oil and filter @ 10k mile intervals. The Taco has had M1 since new, and @ 40k the oil looks very good @ 10k intervals. I switched the 4runner over @ about 150k, and the oil is much darker compared to the newer engine. On the 1st change after the switch to M1 in the 4runner, I noticed that the varnish on the dipstick had been cleaned off below the fill line, which would seem to indicate that the syn. oil is cleaning buildup out. Since oil consumption in this now 200k+ engine is very low, it may be a good guess that the discoloration is more from the cleaning of old deposits than from blowby. It also seems that the oil is staying cleaner in the 4runner with each oil change. I've got M1 on my workbench ready to go in the diffs and tranny of the Taco next oil change

 

you guys that run the 10k mile intervals i hope you are changing the oil filters out at 5k miles or so.... personally i wont do the 10k mile interval. i have about 6k miles on my mobile 1 regular syn and i am going to change that out this weekend. i dont like going over 6k miles on any oil bc of the oil shearing and contaminants that filters cant get out like fuel and coolant.. esp for higher mileage motors.. the only way to be SURE that your oil is good for the 10k miles is to have a 25$ UOA done on it.. i havent seen one mobile 1 syn UOA at 10k miles that looks good enough for me to do it. 4-7k miles yeah but not over that

 

oh and most of the UOA's i have seen with mobile 1 syn showed higher IRON contents that most oils. iron comes from (most of the time) your pistons due to wear.. does this mean mobile 1 syn doesnt protect your motor as well as most others? i dunno but the #'s show theoretically that maybe it doesnt protect as well as you may think.. our 3.4 motors are low wearing motors but still.

 

The owner previous to me used M1 syn and I continue to use it and change it at 8k (filter too) and I just got a compression check and at 130k I am still within 2psi on all 6 cylinders from factory spec and absolutely no leaks anywhere.

 

I'm a fan of Mobil-1 synthetic . I don't always buy it though because it's very expensive and the wal-mart near me no longer carries the larger jugs.

 

Anyone ever try to sign up for the Mobil 1 rewards? Supposedly you can get $5 in gift certificates for every 6 quarts of M1 that you buy so it's kind of like buying 5 and getting 1 for free.

 

no didnt know that.. does it count for the 5 qt jugs or do you have to buy the individual quarts?

 

I emailed Mobil1 and got this reply:
"The Mobil 1 Rewards program is set up for purchases of six quarts or an
oil change. We recommend you buy enough one-quart bottle of Mobil 1,
which, when combined with your four- or five-quart jug, will be a qualifying
purchase entitling you to rewards under the program rules. Or you can
submit your jugs when the total number of quarts is divisible by six
provided that the purchase dates are within the time range specified by
the program's Terms and Conditions. It is acceptable to hand-print the UPC
numbers onto a piece of paper to include with your submission paperwork
if the numbers are imprinted into the bottle or jug material.
Please add a line to your Rewards submission form reflecting the jug
purchase(s).

Thank you for contacting us. We appreciate your use of Mobil 1."

so I guess we could either buy (1) 5-quart jug + (1) 1-quart bottle which is a total of 6 quarts to qualify for $5 in Rewards certificates
OR
buy (6) 5-quart jugs which a total of 30 quarts which if I am doing my math correctly means qualify for: ($5 per 6 quart)*5 = $25 in Rewards certificates

however, when I was looking at how to redeem the certificates, I only saw Pep Boys and not Wal-Mart or Advance Auto as participating merchants

 

I use amsoil in my rigs, sure i have to order it.. but it lasts for 1 year.. and is a much better oil than mobil 1

I havent found a comparison of Mobil 1 and Amsoil, but here is one of Mobil 1 Extended Performance and Amsoil.



This shows the benefit to the Amsoil Filters... Mobil 1 extended performance filters are a synthetic blend

 

Ive been running Amsoil for quite awhile now. Im planning to do a uoa this january to see how shes holding up...this is with Series 3000 HDEO.

 

Do you mean HDD? Thats what I ran for years, and my dad still runs. I am going to the Series 2000 TSO since its rated better with gas engines. My dad has the HDD becuase he has it in his cummins and 454, and wants the whole "fleet" on the same thing .. Great oil.

 

Yea its a great oil and when compaired to the Series 2000 my gas milage hasnt changed. I may or may not stick with Amsoil but if i do ill continue to the Series 2000.

 

Are you guys experiencing any valve train noise when using moble one syntheitc 5W30?

 

Yeah, i do hear a little noise in the valves and from what i have read the mobile 1 seems to have this happen. it did it with both 10w30 and 5w30 so it must just be the mobile one.

 

I was just at Wal-Mart on my lunch break and they have "rolled back" the price of their 5 quart jugs of Mobil 1 to just under $20 (used to be $23.xx). Awesome! It looks like it's the regular price now; not a sale price.

Rob

 

FYI:

the formula of Mobil 1 has changed. It is no longer a full synthetic, it has some dino base formulas.

I recommend Pennzoil Platinum. A VERY good oil with excellent reviews and tests post-engine run.

check out Bob Is the Oil Guy (a lubrication/maintenance forum intensive on oils......M1 isn't all that great anymore)