Not sure about this one. I thought about running synthetic and I know the Mazda says not to but I have heard good synthetics are ok. I thought maybe going with Pennzoil Platinum Fully Synthetic or Royal Purple. Wanted to get some opinions or first had results. Also, what are thoughts on oil weight? I was thinking 20W-50 because I know it is better for cars that will be run under harder conditions.

 

Synthetic engine oil is a waste of money for a street car, but synthetic transmission and differential oil is good because it makes a difference that you can actually feel when driving and it is not changed as often as the engine oil so the cost difference isn't very significant over time.

Most people have found best results with Castrol GTX engine oil. See the owner's manual or the factory service manual for the recommended oil weight for your region's temperature range.

Also, this subject is covered in the FAQ for this section.

 

I just didn't know the first had experiences with it. A local store has synthetics on sale for the same price as regular oil by the quart so I thought I would see. I usually use regular oils.

 

What is the brand and price?

 

unfortunately not all synthetics are created equally, pennzoil is well known as the crappiest and dirtiest oil in the industry and i wouldn't even trust them to make a synthetic that is on par with most others. i run mobil in my bikes(because they share the crankcase with the gearbox and clutch, well except for the duc with dry clutch ), in my cars i run dino oil because synthetics in the crankcase are a complete waste of additional money that can be spent on upgrading or other maintenance so i agree again with EA.

 

It was pennzoil fully synthetic for $3.50 a quart. I didn't know if it was worth it or not. What brand do most of you guys run or have best results with?

 

castrol GTX

 

Just wondering, what is so bad about pennzoil? Is it build up or does the oil break down really easily?

 

both, it's cheap.

 

Pennzoil is bogus synthetic because it is made with Group III base stock. Real synthetic oil is made with the superior Group IV or Group V base stock.

You can read about the bogus synthetic naming convention here:
http://www.pecuniary.com/newsletters...csdefined.html

Street cars seem to run best with Castrol GTX non-synthetic in the engine. Most professional rotary-powered race cars use synthetic engine oil, with Idemitsu being the most common brand, although Red Line and Royal Purple are also popular, and some people use other brands like Amsoil and Total/Elf.

Just about any synthetic oil is fine for the transmission and differential, but the most common brands are Red Line, Royal Purple, and Amsoil. Mobil 1 had a problem with eating synchros several years ago, and although they say that the problem is fixed, many people are still reluctant to use it in the transmission.

Synthetic grease also works well for the wheel bearings and other parts of the car. I have used Mobil 1 and Royal Purple synthetic grease over the years with good results. I plan on trying Amsoil next.

 

Dont get Pennzoil's Synthetic oil, its one of the crappiest Group III oil money can buy. Hell, even their "Regular" oil are full of crap.


There are only a few "true" Synthetic oil on the market.

Redline (V)
Royal purple (IV)
Elf (I think its V)
Amsoil (I think its IV)
Eneos (V)
Mobil1 (some are true IV, some are not. depends on which one)
Idemitsu (I think its IV)

Thats all I can think of right now.

If you want good Mineral/Dino/Regular oil. Castrol GTX is not a bad choice. oh, use 20w50 if your local temperature never drops below 40f.

 

Cool. Thanks for the advice guys. I never knew pennzoil was that bad. I learned something new haha.