Fuel / Tyres

[pommy_golfer]

Went to get a pink slip on Firiday from a mechanic i picked randomly from the big yellow book....

I got chatting to the mechanic who seemed very knowledgable in his trade, he talked alot about alot but it all made sense to me and opened my eyes! Hes been into cars since he was a kid and hes 50 years old...he used to drag cars and was always at track days etc....he has a car that owes him 200,000 bucks. and these are a few things that he told me.....

DO NOT put any other fuel in your car except Mobil or BP Fuel. He told me that these 2 fuels are imported from USA and are very good, all the other ones such as shell, caltex and all the others come from Malaysia and you might as well P1ss in your tank. He said to throw away those dockets that you get as what are you really saving? $1.50? The damage that these fuels are causing your engine will cost you a hell of a lot more. He said if you dont believe me....fill up with the **** fuel, see how many K's you get out of it, and do the same with the good stuff and you will get an extra 80Ks out of the same amount.

INFLATE TYRES TO 40Psi....He said that tyre companies advice to put lower pressures in their tyres so you caome and get another set. He said tyres are designed to put 40psi in them which will see alot more use and is better for the car as its less strain on the joints etc....

[static1800]

Correct if im wrong but some mobile servo's are actually supplied by caltex?

[syncro]

I'd find another mechanic.

[DubSteve]

Hahahahaha!!!

[sukebe]

All fuel companies in Australia (and across the world, I assume) use exactly the same petroleum (it all comes off the ships through the same pipelines, is refined using the same methods, and is distributed through the same holding terminals). The only difference is in the additives (and this difference is minimal) which are usually added in the transport tanker after it has picked up the fuel from the terminal. I have conducted several environmental assessments at the Shell and Mobil Terminals in Newport, and I have seen Mobil and Caltex trucks filling up at Shell, and Cootes trucks (who distribute to various outlets) fill up at both. Where fuel can become dodgy is in independant services stations where internal controls are limited and operators add cheaper, inferior, and potentially damaging products into their onsite tanks as a way to boost profits.

Argument between comparable products from any of the major petroleum producers is, for the most part, little more than marketing. I choose not to buy from Shell on ethical grounds, and usually buy from BP or Caltex as their environmental protocols are sounder (though still dubious).

[zjm]

run 40 psi in a nice wide tyres and watch centre of tyre wear out

[brackie]

Sure... the higher the tyre pressure the lower the rolling resistance and so the better the fuel economy and (marginally) the performance. As a tyre flexes it compresses and decompresses the air inside which heats it up and increases the pressure anyway. So try checking you pressures cold and then after doing 50km or so. It's no accident that you see shreds of truck tyres by the side of high-speed roads but none in the suburbs or on slower country roads.
Hard tyres give less grip. If you take it to it's logical conclusion how well do you think a tyre would corner if it were solid? Also, the flexing of the tread is dependent upon the relative softness of the tyre walls as the profile changes when cornering. The higher the pressure, the less the flex. If you want your 4WD or tractor tyres to give more grip in sand just deflate them and allow them to flex more.

So yeah... the manufacturers' recommended pressures will always err on the side of caution, but the relative difference between what they recommend for front and rear tyres should be adhered to as this is important for the balance of the car. I run my diesels' tyres at 5psi more than recommended and have had no problems with uneven wear or poor grip. I imagine that my fuel consumption would be slightly less but I haven't tested it.

Any professional opinions out there

[The_Hawk]

I have friend who claim that [insert random company] (Shell, Caltex, BP) are good or bad. This to the point where one mate wont use Shell because he says it rubbish and causes problems he notices when driving.

Considering we are talking about only the local few servos and not a range of different ones (say every Shell within 50kms) it's pretty much what sukebe has said and is more about the local boys put in the tanks as additives.

While I'm not the expert and don't want to diss your mechanic, you have to wonder how much of this is simply one or two bad experiences he has personally had 20 years ago that have soured his judgement? People are fickle and don't need alot to get them offside.