2 Maintenance Questions

[notsobigkahuna]

1) what oil are people running in their v6? Anyone using synthetic or semi synthetic?

2) what tire pressures are people running?

Thanks

[Skydancer2992]

Depends on the amount of driving. The full synthetic will yield a slightly better gas mileage due to its superior tribology but the higher cost may outweigh the savings.

The priority should be to warm up the oil periodically to keep the condensation out or to keep the oil refreshed.

Carbon in the oil combines with water to form a weak acid. Water can also absorb other impurities to coagulate or foam, reducing the effectiveness of the oil's friction reduction.

[Maineah]

Personally I would stick to conventional oils and standard service for a couple of reasons. The MH works hard it is just about to the max every time you go for a ride using a syn. blend is a total waste of money if you drain it before the recommended interval. If you change the oil with conventional oil it will offer you more time to check every thing out on the MH belts, hoses, tires, grease fittings, drive line etc.these things are getting to be antiques and over the years they have taken a beating and need looking after. I ran 50 psi all around that seemed to give me decent mileage and a good ride. There are no more than 3 companies in the US that make a syn. oil there are many that make a syn. blend and all of them tell you they are syn. oil. If you have a high performance turbo/super charged car or run it on the race course you might need a syn based oil.

[fred heath]

:-)

[notsobigkahuna]

I use synthetic in my pathfinder because that's what has always had, I bought it used. I watch for the synthetic to go on sale, after at 40% off, makes it about the same as conventional. 5L for $30 give or take.

Thanks for the

[notsobigkahuna]

Oops, response.

[Vanman]

I use Mobil 1 high vehicle mileage in everything I've got, 10-40 in the Toy and 10-30 in the Ford. Subaru is 5-30, but not the High Vehicle Mileage blend. There is a large post about the various types and blends elsewhere on this board. Makes a good read.

[zero]

1) what oil are people running in their v6? Anyone using synthetic or semi synthetic?

I'm running oil that is sold as "full synthetic", but as far as I'm concerned, it is NOT. So I guess the answer to your question depends on what YOUR definition of "synthetic oil" is? Last I checked, there are only two major countries in the world where is it legal to sell motor oil made from 100% petro-oil base-stocks and then sell it as "synthetic."

The original definition of "synthetic oil" was for oil NOT made from petro/mineral oil. Thus the reason it wall called "synthetic." Not anymore. At least not in the USA or Canada. Adolph HItler was one of the first to have it developed. Then the US Military adopted it during WWII for use in jet engines. Why? It's ability to work in wide temperature ranges and an extremely high "Flash Point." "Flash Point" is its high-heat durability. When WWII was over, a military guy named Colonel Amatuzio (jet squadron leader) started marketing TRUE synthetic oil to the public as "Amsoil." Not long after, Mobil did the same with their "Mobil 1" product.

Now the market is flooded with oils sold as "synthetic." Some are and some are not. My point being that if someone tells you they are using it, ask for specifics. What brand, type, and for what gain?

I've read the great claims about many oils sold as synthetic and for some - the claims are pure BS. I could go on with details but it gets long and boring unless we are talking about an actual head-to-head comparison with specific brands and types.

Last I read data sheets - Amsoil was one of the few still selling genuine synthetic oil for highway vehicles. Many companies sell it for off-road use and racing.

Group III processed mineral (petro) oil is used in many, many "synthetic oils" sold in the USA.. A true synthetic would be made from something like Group IV basestock (PAO). Many of the oils that Amsoil sells DO use PAO. USA and Canada versions of most types of Mobil 1 sold in the USA for highway use still use good-old mineral oil.

Again - I suggest when searching for info you ask for specifics. Lots of BS and general claims being made about stuff being called "synthetic."

I'm using Mobil 1 so-called "synthetic 10-30W High Mileage in two vehicles but not my Toyota RV.The reason why I'm using the Mobil 1 is for these reasons.

#1. Stabil viscosity over a wide temp-range. I've got it in two vehicles that get started in temps as low as 30 below zero F up to 100 degrees F.

#2. Extra ZDDP additive package for metal wear that has nothing to do with being called synthetic or not.

Both my Toyota RVs (2.2 and a 2.4) have Shell Rotella 15W-40 in them. I only drive them in the summer/fall so the viscosity range is not an issue. Also since Rotella is a petro oil for heavy-duty use - it also has a high ZDDP additive package for metal-wear protection.

For myself - for any older vehicles I use in fairly warm weather only - my main concern with oil is the metal-wear preventative additives. Many oils made for cars and trucks have those additives lowered. Older rigs like our Toyotas were designed for oils with high additive levels of ingredients like ZDDP. To get that you have to pick and choose carefully. They come standard in most off-road and/or heavy duty oils but not standard auto oils anymore.

[Maineah]

Conventional oils run between $14 - 19 up here depending on what's on sale. Syn.blend about $10 more. I do the oil in my 2011 Tacoma at 5K with dino oil gives me a chance to check every thing. Did the same with my old 97 2.7LTacoma for 285K till I sold and bought the new one. Never used syn. never lost an engine in any of the Toyota's and I don't get rid of them until they have at least 200K on them.

[notsobigkahuna]

I know that some of my vw westfalia pals have switched to rotella for the zinc. I think I read somewhere that not all rotella has the ZDDP any more.

Thanks all, interesting.

Kahuna

[darrel]

I use Pennzoil synthetic and run 60PSI all around.

[WME]

Need extra ZDDP?

http://www.ebay.com/sch/i.html?_from=R40&_trksid=p2050890.m570.l1313.TR0.TRC0.H0&_nkw=zddp+oil+additive&_sacat=6000

[Vanman]

EDIT FROM BEFORE:

On the Toy 55# rears, 48# in fronts. That's much higher than the dataplate on the Toy says, don't know how they got to that, thou Hankook said to me in an e-mail

"I have had some difficulty finding a digital chart to email to you. However, I have done some calculations based on my reference materials and the loads that you estimate each tire will need to carry. I have come to the conclusion that the vehicle conversion manufacturer has provided you with quality tire pressure recommendations.

Front - 36psi (248kpa) = approx 1200 lbs of load capacity per tire (single application)

Rear - 45psi (310kpa) = approx 1400 lbs of load capacity per tire (dual application)

You can increase inflation according to additional loads and tire wear "

so go figure??? They sure look too flat for me at those pressures.

[Vanman]

Does the ZZDP have any effect on the wear factor of cold oil, ie: cold oil not up to running temperature???

[Maineah]

EDIT FROM BEFORE:

On the Toy 55# rears, 48# in fronts. That's much higher than the dataplate on the Toy says, don't know how they got to that, thou Hankook said to me in an e-mail

"I have had some difficulty finding a digital chart to email to you. However, I have done some calculations based on my reference materials and the loads that you estimate each tire will need to carry. I have come to the conclusion that the vehicle conversion manufacturer has provided you with quality tire pressure recommendations.

Front - 36psi (248kpa) = approx 1200 lbs of load capacity per tire (single application)

Rear - 45psi (310kpa) = approx 1400 lbs of load capacity per tire (dual application)

You can increase inflation according to additional loads and tire wear "

so go figure??? They sure look too flat for me at those pressures.

There should be a coach manufactures plate on the frame behind the drivers door that has the tire pressures for the extra weight after they put the body on it. 65 psi is the rated pressure for an "E" rated tire, load range 80 for a "D".

[Derek up North]

http://toyotamotorhome.org/forums/index.php?showtopic=4680

[linda s]

Don't you have that backwards? 65 for a D tire and 80 for an E. I think many of the coach manufacturers suggested tire pressures are ridiculously low.

Linda S

[Derek up North]

That's much higher than the dataplate on the Toy says, ...

Could you please let us know the Make and Year you've got and what pressures and tire specs are marked on the dataplate? And is there any indication on the plate if it's info from Toyota or the manufacturer.

[zero]

I know that some of my vw westfalia pals have switched to rotella for the zinc. I think I read somewhere that not all rotella has the ZDDP any more.

Thanks all, interesting.

Kahuna

No the "Shell Rotella T Triple Protection" has not gotten the ZDDP lowered. It's the other versions.

Like "Shell Rotella T3 CJ4" and "Shell Rotella T CJ4 Plus."

The old standard for heavy duty use and high ZDDP is still pretty much the same as it used to be. That is Shell Rotella T Triple Protection" and it only comes in 15W-40 or 10W-30.

[zero]

Don't you have that backwards? 65 for a D tire and 80 for an E. I think many of the coach manufacturers suggested tire pressures are ridiculously low.

Linda S

I don't think the coach makers had any say in the matter. Recommended tire pressures to coach builders were given by Toyota. I've got the Toyota cab & chassis coach-builders books here for most years from 1977 to 1991 for the USA and Canada. Also up to 2006 for overseas single rear wheeled HiLux cab chassis combos. For 185R-14C tires and a 5500 GVWR, Toyota shows for a truck/coach with max load - 45 PSI in the rear with duals and 64 PSI with singles. 26 PSI for the fronts with either.

[Vanman]

WRONG WRONG WRONG sorry see new post !!!!!!!

[linda s]

Yeah I think the 26 lb pressure is what made me think it was ridiculous. At that pressure my tire looks completely flat. No thanks. I'll just keep mine over-inflated at 50

Linda S

[Vanman]

"recommended" tire pressures are a joke from most manufacturers. The Subaru Outback forums have an incredibly long sticky post about what a horrid POS the stock tires are. Recommended is 32# front 30# rear from clueless SOA (Stupids Of America). Hard driving will just make the front end push like mad with no road feel and a howling noise if you try to tighten your line at all. Classic underinflation, I settled on 35# all 4 and what a difference!!! It's still not a good tire but the holding and now nimble steering make it fun to drive hard in mountain roads.
But the new Michelin Premier A/S shoes are sooo much better, I've yet to even get a squeal from them and they like running at 35# also.

[warrior maintianer]

Good Morning Linda, I had a repair shop for 25+ years and tire psi is a pet peeve of mine. Tire technology has changed over the years so using an old reference is of no value. Tire designs have changed and tires typically now run at higher psi with thinner side walls for better millage this make old recommendations in manuals and on doors incorrect. Every tire has markings on the sidewall they will tell you the max psi & the weight the tire is designed to hold at that psi. Usually the higher the load rating the more weight the tire will hold but it is at a higher psi. The less psi in a tire the less weight it can carry the danger with a underinflated tire is that it will run hot!!this will cause it to fail. AN old tire guy showed me long ago that a failed tire will usually have something in it that caused air to leak and the tire to run soft & hot I have found this to bee true. You can start bye inflating the tires to their recommended max see how they look. often vehicles such as ours are pushing small tires to the max and need to be at this psi.

For my money synthetic oil is worth the money, the improvements in lubrication over the years has really made a difference in longevity. I like Castrol syntec right now 0w-40 seems to be easy to get I find Walmart is an good place to get oil my last 5qt jug was $21.99.

[linda s]

Yes maintainer guy. It's never been an issue for me. I have always run the front at 50 and the rear at 55. If you read the docs JD posted it also says max curb weight for the Toyota cab and chassis is 3500lbs. Most Toyota motorhomes weigh in at a ton more than that. Common sense rules by me. If it looks flat, it doesn't have enough air in it. I do believe my duallies would touch in the back at 46 lbs pressure. Not something I would risk

Linda S

[zero]

Thats what it says. 200a is the National info # I guess, what does the MPV mean

class of RV ??

In North American, "MPV" denotes "multi purpose vehicle." The D.O.T. requires that anytime a passenger tire is used on an MPV - tire pressures are to be increased by 10%.

[zero]

Yes maintainer guy. It's never been an issue for me. I have always run the front at 50 and the rear at 55. If you read the docs JD posted it also says max curb weight for the Toyota cab and chassis is 3500lbs. Most Toyota motorhomes weigh in at a ton more than that. Common sense rules by me. If it looks flat, it doesn't have enough air in it. I do believe my duallies would touch in the back at 46 lbs pressure. Not something I would risk

Linda S

I think you are misinterpreting the Toyota specs. The tire inflation tables are for a Toyota cab& chassis with an added coach with a max total load of 5,500 lbs. NOT the "curb weight."

Toyota gives an official "curb weight" of 3510 lbs. for EPA fuel efficiency ratings. If a coach-maker builds an RV that results in a curb weight over that 3510 lbs. - the Toyota fuel-economy values are null & void. It has NOTHING to do with tire inflation. Such fuel economy tests are done with a max 3510 lb. truck/coach, two fake humans weighing 167 lbs. each, and 300 lbs. of cargo. Total weight for test - 4,144 lbs.

Toyota recommends for a fully loaded cab/chassis/coach with single rear wheels and a load of 5,500 lbs - 26 PSI in front and 64 PSi in back. If dual rear wheels - 45 PSI.

As I understand the Toyota manuals - coach builders can raise the tire PSI ratings over what Toyota calls for if appropriate tires are used. However they are NEVER allowed to lower PSI below the Toyota specs.

Note that a typical 21' Toyota RV in the real world can weigh 6000 lbs. Engineers also figure in front to rear weight shift of 10% (or vice-versa). So such a "real world" overloaded Toyota RV can had, let's say 1800 lbs in front and 4200 lbs. in back. Adding that 10% bias that comes to 1980 lbs. front and 4620 lbs. rear. That amounts to a worst-case scenario of 990 lbs. on each front tire. 1155 lbs. per tire on the rear with duallies.

So what do tire makes say for pressure to get the correct tire profile as designed for 185R-14C 8 ply rated tires?

For the front tires at 990 lbs. it is 28 PSI.

For the rear tires at 1155 lbs. each it is 30 PSI each.

Then you can add things like safety and redundancy - like if one tire in the rear goes flat -then the remaining single tire can still handle the load of two which is 2310 lbs. So at 2310 lbs. - the best you can do is the max inflation of 65 PSI that is rated 1874 lbs.

I know one thing for sure. Nobody can just look at a radial tire and tell if the inflation is correct by the way it looks.

[linda s]

Blah Blah Blah. Not the pressure I would run my tires at no matter what those very old documents say. I wouldn't run a Honda with only 26 lbs pressure

[shibs]

Yes maintainer guy. It's never been an issue for me. I have always run the front at 50 and the rear at 55. If you read the docs JD posted it also says max curb weight for the Toyota cab and chassis is 3500lbs. Most Toyota motorhomes weigh in at a ton more than that. Common sense rules by me. If it looks flat, it doesn't have enough air in it. I do believe my duallies would touch in the back at 46 lbs pressure. Not something I would risk

Linda S

Linda,

Thanks, I put in the 3x lb in my tires and was wondering what the flip...they looked flat you mentioned it.

I am 40 lbs in my Honda in summer, little bumpy but I get great mpg :-)

Lol, the previous owner actually complained that one of his rear tire failed as they were rubbing, no wonder, he had the tires at 30 lbs.

[shibs]

I use whatever (major brand) synthetic oil is on sale in my gas vehicles.

JDE is on the money, few PAO based synthetic oil out there, I used to use redline in my racing mazda rotaries.

Dino oil works FINE, just change on time.

I use synthetic in my gassers cuz:

1. I idle a lot, sometimes 20 hours a week

2. a lot of 2 block trips

3. changing oil is the last thing on my mind,

but the main reason is cold temp flow,

toyos will run fine with either dino or syn.

[zero]

Blah Blah Blah. Not the pressure I would run my tires at no matter what those very old documents say. I wouldn't run a Honda with only 26 lbs pressure

Is "blah, blah, blah" a technical term I'm not privy to?

[zero]

Lol, the previous owner actually complained that one of his rear tire failed as they were rubbing, no wonder, he had the tires at 30 lbs.

Why do you think 30 PSI in a rear tire would cause a failure? Toyota calls for a minimum of 29 PSI in the rear tires if a dually with 6 ply tires and up to a total vehicle weight of 5500 lbs. At 29 PSI, each tire rides at the designed/desired profile when it has 1,099 lbs. on it. There are four of them, so at 29 PSI the tires ride correctly with 4,396 lbs total on all four of them.

And yes, I know. Linda says "blah-blah-blah" to such things. Personally, I tend to believe such published specs done by engineers with convoluted calculations and formulas. God help us when technicians start designing things solely by what "looks right."

I also disagree that Toyota factory tech specs from 1988 and 2004 are "old' and not to be trusted. Nothing much in this context has changed since then.

[shibs]

Why do you think 30 PSI in a rear tire would cause a failure? Toyota calls for a minimum of 29 PSI in the rear tires if a dually with 6 ply tires and up to a total vehicle weight of 5500 lbs. At 29 PSI, each tire rides at the designed/desired profile when it has 1,099 lbs. on it. There are four of them, so at 29 PSI the tires ride correctly with 4,396 lbs total on all four of them.

And yes, I know. Linda says "blah-blah-blah" to such things. Personally, I tend to believe such published specs done by engineers with convoluted calculations and formulas. God help us when technicians start designing things solely by what "looks right."

I also disagree that Toyota factory tech specs from 1988 and 2004 are "old' and not to be trusted. Nothing much in this context has changed since then.

JDE, I am just quoting what the owner passed on to me, you make a good point, after reading your post I agree that at 30 lb the tires should not be rubbing.

It could be that with the change in temps, 30 lb in summer could be lot lower in fall (1 lb/7 deg F). Hence my apprehension about keeping the pressure at factory spec.

Long story short, I am going to recheck my sidewall pressure rating and air them up to max:

it is going to take a while as I have a tiny 800 w generator and a 1 gallon pancake compressor.

I drive my diesel with 60 - 80, I am going to 80 - 80 this summer

[Maineah]

They may not rub but it's kind of hard on the side walls. Don't forget a 6 ply rated tire does not mean it has 6 plys.

[Vanman]

The data location is behind the drivers seat not on the door jamb.

It's from National RV:

date of manufacture by National 8 / 91

date of INC, MFG is 3 / 91

G.V.W.R. 6000#

G.A.W.R.

front 2300# with 185R14tires, 14X5J rims, at 36# PSICOLDSINGLE

rear 4400# with 185R14 tires, 14X5J rims, at 45# PSICOLD DUAL

THIS VEHICLE CONFORMS TO ALL APPLICABLE FEDERAL MOTOR VEHICLE SAFTEY STANDARDS IN EFFECT IN : 3 / 91

V.I.N JT5VN94T7MOO.....

TYPE MPV

200a

Thats what it says. 200a is the National info # I guess, what does the MPV mean

class of RV ??

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91 Dolphin 400 94 Aerostar 08 Subaru H6 Outback

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#22 [2 Maintenance Questions: post #22]

SEE CHANGE TO REAR PRESSURE SORRY !!!