How about single grade oils like SAE30 or SAE40? I just
loaded up my T2 with Castrol SAE30 today to see how it
does. My take on it is that a multi-viscosity oil has
more 'troublesome' additives & detergents than a
simplex viscosity oil.

I live in Orange County, CA so I can safely say I'll be
above 40F at all times. I drive in a lot of traffic every day
so I'm banking on the simplex oil to hold up a little
better than the multi-grade stuff...

 

I use Castrol GTX 10w-40 year round. But then again I live in New Mexcio seems like summer year round :P

 

i ment New Mexico (cant spell)

 

IMO all that SAE30 is doing for you is increasing engine wear upon startup. I wouldn't use that 30wt once the temperature in your area gets back up to the high 80's / low 90's in July-Sep. IMO 20w50 is the best grade for year-round use in warm climates.

From the Valvoline web site:
"Singlegrade oils will become obsolete for performance engines in the future. We dropped SAE 30 and SAE 40 because SAE 10W-40 does everything 30 or 40 can do—and some things the straight grades can't do—like increasing horsepower. If an off-roader doesn't like SAE 10W-40, then use 20W50. It can do everything a SAE 10W-40 can do except pass the sub-zero viscosity test at -20 degrees C."
http://www.valvoline.com/carcare/art...=ccr20010101ov

 

Evil,

Thanks for the info! I'm in total agreement that I ought to use something a little 'thicker' in the summer months. I'll check out the link you left and give it some thought too. I'm not so sure that 30 weight is that much more of a problem at start-up than the 20w side of the 20w-50 oils. However I also won't proclaim to have any significant in-depth knowledge of the subject either and I'm always open to suggestion. I was planning on running the multi-grade next after this oil change interval is up to see if I noticed any differences. I will say that the turbo likes the light weight stuff better, it seems to require more electronic 'intervention' on the wastegate now that I'm running the SAE30.

 

I use 10-40 mobile one.

works great!

 

20-50 Castrol Gtx in Summer- Best oil presure, & runs best .. N/w Pennsylvania ..$ 5.00 walmart , Garaged all winter .. right on Hummer .. my machanic of prior A gas coupe, with hemi's, blueprinted Rat motors, ect . Went the far extream to issues of absolutely never! mixing oils ..Moliicules issues ..ect Bottom Line is What works in your perticular Climate, motor Application & your Driving Habbits & Conditions ??

 

I use 10w-30 Castrol GTX for my N/A.

 

Just a pionter of those who use sythentic...Premix atleast 6 oz's in the the tank everytime, or block of the oil injectors...synthetic really does increase engine wear by increase carbon...my self I use 20w-50 Advanced Auto Parts Oil.. only 88cents per quart and I change it at 1500 miles change my oil filter every other oil change...I belive that 20w-50 protect engine parts much better than lower viscosity oil, granted it will give you less hp...

 

i have a 88 convertible and i use 20w50 year round na turbo . when its 10 out or 100 out i use it . and everything is fine its better then using 10w whatever

 

I hate to tell you this but Castrol is no better. Castrol doesnt have its own refinery. It buys the cheapest oil from whoever they can. It sludges horribly. I've seen the sludging personally. But I didnt know why. I asked my manager and he told me thats why. Cause hed seen Castrol do the same thing to his Chevy big blocks and he got curious and did some research. I dunno, thats what I was told, but I have seen it sludge.
The only thing I use in my T2 or ANY of my cars for that matter is Mobil 1. They've been around forever. They have their own refinery. They know what their doing. I use the 15w-50 synthetic in the rotary. And of course I use the Mobil 1 filter in conjuction.

 

I am about to put castrol GTX 10w30 in my turbo...FL, is this ok?

 

10w30 in Florida? I'd go thicker if I lived there or I'd use a synth.

10w40 Mobil1? Where did you get that?

Synthetic doesn't increase engine wear!

I also have no faith in straight weight oils considering the crazy weather patterns in this country. Stick with something with a "W". All oils have detergents and additives. Just because its a straight weight doesn't mean it doesn't have detergents and additives.

I have also mixed oils(weights/brand/types) in numerous cars with no molecule or engine issues.

There is nothing wrong with using a 10w40 in a high revving engine.

 

I use castrol 10w30 in the winter (well, I just did use it, but Im gonna find a synthetic around that) and mobil1 20w50 syn. for summer.

 

only if it doesn't get any warmer than 80F in florida.

 

I dont think it gets any colder than 80F in florida

 

Ahhh why is Toyota and GM voiding engine warrenties on engines that have 10W40 in them then???

 

There aren't too many GM/Toyota rotaries, are there?
As far as I know, anything but 5w30 or 5w20 with MOST new automakers IS an issue. GM/Toyota would probably say the same with 20w50? or any other thicker weight?

Any idiot telling the dealer what oil weight they use should get their warranty voided based on their own stupidity, especially since these newer engines are running tight clearances with almost perfect tolerances within those clearances, hence the requirement for **** thin oil.
I haven't seen any dealer or factory rep sample the oil for a warranty claim. Even if new car dealers sampled the oil, how can they prove that the oil is just the required thin oil that has thickened with the crazy(7.5-10k+) oil change interval that new cars have.
People should shove there foot in their mouth when visiting dealers for warranty work.

10w40 synthetic has been working great in my car. I am trying to debunk all the BS by running synthetic because everyone thinks its bad, and by running 10w40 because it is so destructive. Both claims are nothing but hearsay!
I also haven't been able to create brown death in a boinger equipped car with a certain brand and weight of oil.

Seems to me that the most oil related deaths are caused by infrequent changes and poorly chosen weights with regard to weather. 20w70 shouldn't be used by Santa Claus and 0w20 should be avoided by desert rats. A little common sense + frequent changes would've eliminated all oil BS concerning brand, weight, type, etc.

And to make things worse, I will be switching to a 10w40 vegetable based synthetic motor oil by the end of the summer.

 

Synthetics are a whole other issue, and I believe we have proven long ago that a good quality synthetic (Mobil 1, Redline, Neo, Royal Purple) is perfectly fine to use, just stay away from the crappy ones like vavoline penzoil and the like.

As far as my comment on the 10W40 it was too the conventional oil crowd. There have been serious issues with higher reving late 90s motors using conventional 10W40 and 10W50. They do not burn as clean, they do tend to gumm/sludge up and other issues all related to the extra polymers used to get that viscosity range due to the low base oil stock. That is the difference though between a 20W50 and a 10W40. Although both have the same differential, the base stock of the 10W does not lend itself well for a high viscosity and considerably more polymers must be added.

In this case it's not a situation of engine type, it is a situation of what is added into the oil and clearences of engine parts.

Based on two of the biggest auto manufactures in the world, and their results, I can not ever suggest that anyone uses a conventional 10W40 or 10W50 on any modern engine. Because rotarys are even more sensitive to engine oil quality and ash content, I would be very very concerned about anyone fool enough to use a conventional 10W40 or 10W50.

 

I have always stuck to 20w 50, works great for me!

 

Ok, I'm a n00b,

I'm picking up my 89 GTU in july....

I live in NC (Raleigh to be exact) where we have sub 20 degree winters, and 95+ summers.

I have NO experience with rotaries, but with my gt stang, i used 20W-50 all year, anything less and the valves clinged and clanged like jingle bells.....

anywho, I really don't want to blow an apex seal, or anything like that. Should I use a different oil in winter than summer? Are rotaries that needy? I kept the 20W50 in the stang all winter and summer, and never had a problem. I really don't want to take a chance with this car.

Thanks,
Jonathan

 

i was under the impression that the 10 and the w and the 40 had a value in measurement...and that 20 w 50 was the cleanest burning(in the combustion phase)...while allowing the most protection in the unburning areas of the rotary...basically i thought i was using 20 w 50 because it has less additives so it burns better/cleaner..lower ash etc.......and that synthetics, have higher ash/additives and leave gummy deposits at a hugely higher percentage/rate..isnt that why they designed the #w# values..to designate additives (which acheive the viscosity)...anyways or something close?...i cant quote cuz its been years since i researched this stuff...but i thought it was along those lines...go ahead and flame me if im way off!! ill take my beating...unless im pretty close then...well...then ill take the flaming but sit in front of the comp and **** and moan about it...and you dont want that...lol

ive been using 2 cycle oil in my 7 for years...no premix just let it go right in the motor..**** is clean!! no probs. it goes against what the factory says but who cares...someone on the board says its cool so do it...what have you got to lose? the gains are tremendous!! my singel cars experience is way more supporting than the several generations of testing mazda has done on rotaries....just believe me ive got a bunch of posts so i know!!


the tornado air circulator adds hp too!! just as much as a turbo and its cheap!! do you buy that?

ho hum just rambling on about nada

 

Poorredneck, sounds like your stang needed a rebuild. I've seen plenty(5.0's, 4.6's) run thinner oils with no problems. Could also have been a filter or oil pump issue.
The rotary needs more frequent change intervals for long life. Weight should match your weather patterns.

goblues24, Oil company additive choices have to do with the quality of base oils they use and their ratios. With the various base oils available, it is possible to make almost any oil weight without needing so called polymers, that everyone mentions, but rarely seen as a percentage in the oil's formulation.

Concerning the motor oil weights, the 1st number is a test at a cold temp(6 different tests different for each- 0w, 5w,......25w), and the 2nd number(20.....60) is a test at two different higher temp numbers.
Gears oils have different tests and temps and don't relate well with motor oil weights even though people compare the two.

Ash, gum, gunk, sludge, all have to do with the oil brand chosen and their formulation. There are synthetics and minerals oils that gum/sludge up. And there are synthetics and mineral oils that don't. Brand choice and not weight choice is the cause.

With the 100's of blown engines mentioned in the threads in this forum, and with 46% of people running a 20w50 motor oil(from above), it would be a somewhat logical conclusion that more engines blow because of 20w50 than any other weight.
I'm waiting for the thread that polls oil weight used when engine was blown!
More specifically, since I don't believe oil weight as a big issue, I believe that a thread polling brand chosen and maintenance interval will lead to a common cause of engine death!

 

is that valvoline VR1 oil good for a 86 Gxl with 90,000 miles

 

bump