Which Gas for our trucks???

[70cst]

http://www.toptiergas.com/index.html



Top Tier Detergent Gasoline...
Most likely this topic has been discussed before but I found this on the Subie sight and I thought you might find this of interest. I guess the question is will the 402 and 350 engines have the same operating charateristics if both were using the same gas?

[68gmsee]

Not sure what your question is. If it's about the gas, I usually get the better gasoline and avoid any that have alcohol. I also don't get gas at the local stop and go stores unless it's an emergency.

The type of gasoline octane you use will depend on the engine requirements. If it runs better with the higher octane then I'd stick with that. In my case, I have always used the regular lower octane since my trucks have stock lower compression engines at this time.

There have been a lot of posts about adding additives to protect the valves, etc. I've been running mine for many years without any problems. I figure when the valves give out, I'll do the work then.

[70cst]

I guess I was asking if there was any real difference between gasoline manufactures? Are they all the same? I know some private label their gas. Some say Shell is the better brand while others say there isn't much difference. Octane ratings should make a diifference I would think. ie: 97 verses 91

[T/C]

Originally Posted by 70cst

I guess I was asking if there was any real difference between gasoline manufactures? Are they all the same? I know some private label their gas. Some say Shell is the better brand while others say there isn't much difference. Octane ratings should make a diifference I would think. ie: 97 verses 91

I have no clue on the gas thing... To me it seems like other then them adding things to the gas that it would all be the same?? But as i said i dont know lol uneducated guess..

On the Octane... The Lower octane you can run the better... If thats what you were asking... If not ... Ignore me lol

[nick_stewart2001]

i hvae a 69 c20 with the 292 I6, i was wondering is it necessary, beneficial, to run lead substitute in these engines? i just got the truck, dotn know much about vehicles this old. thanks

[68gmsee]

Originally Posted by nick_stewart2001

i hvae a 69 c20 with the 292 I6, i was wondering is it necessary, beneficial, to run lead substitute in these engines? i just got the truck, dotn know much about vehicles this old. thanks

On my 68 with 250 I6 I run regular gas with no additives. On my old 69 with 350 I did the same. A machinist told me he had a 66 six cylinder with a lot of miles and had been running it with regualr gas for about 10 years with no problems. His answer when I asked about replacing the valve and seats was that when the valves go, it's time for a rebuild anyway.

Now, if you have a nice rebuilt engine with low miles and you want to prolong the rebuild, then adding lead may help. Also, the type oil you use will help. Some recommend the higher zinc oils like the ones used in diesel engines.

[Sinister]

I run gas from the big guys, Shell, 76, Chevron or Mobil. Texaco if it's around. I had a friend who worked in a shop who's specialty was rebuilding carbs, told me that cheap bargain gas was garbage. Gummed everything up. Don't know if that's true or not, but he definitely knows cars/trucks.

[nick_stewart2001]

please forgive me, im a youngin' and not used to all this old school stuff even tho i love it! the engine is low mile 60,000, but original, whats a higher zinc oil? i thought the PO said he used 15w40 i know thats a diesel oil. so id really to know how to best tke care of this engine, the truck is my daily driver

[cdowns]

if it's an engine more than 25yo i doubt gas of anykind will make any noticable difference

[70cst]

Good feedback. My 402 has been rebuilt to tin om unleaded.

[68gmsee]

Originally Posted by 70cst

Good feedback. My 402 has been rebuilt to tin om unleaded.

In that case you'll just have to try different companies to see which one makes the engine run better. I'd probably stick with the better gas like mentioned above.

Originally Posted by nick_stewart2001

please forgive me, im a youngin' and not used to all this old school stuff even tho i love it! the engine is low mile 60,000, but original, whats a higher zinc oil? i thought the PO said he used 15w40 i know thats a diesel oil. so id really to know how to best tke care of this engine, the truck is my daily driver

Just so we don't hijack 70cst's thread, do a "search this forum" above and enter "type of oil." Look in there and there's a post on what type of oil to use. It's really nothing to worry too much about.

[MudBug]

The EPA made them take zinc out of oils to save cat.converters.Most car builds have gone to roller cams so the zinc is not needed to lubricate cams and lifters.Rottela has zinc in it I think.Its used in diesel engines.

[Pont406]

I run ARCO 87 in all my vehicle but a Ventura. That one gets ARCO 91.