What is the best oil for the beast.

[soslow]

With the issue of taking zinc out of the new formulted oils, I need to know if anyone has the definitive answer for using an oil with the best protection for our beloved LT-5 that will provide the necessary protection that the old oils used to. I don't want to use a zinc additive because it has been reported that it destroys the catalytic converters.

[XfireZ51]

I'm using the Castrol GTX 15W-40 Diesel. It has the levels of zinc etc that everyone's been talking about here at $4/qt. No additives necessary.

[Hammer]

I think I'm going to try the Valvoline VR1 10-30 next time around. High zinc and phospherous and Marc H. said it would be a good oil. Hard to get though, not readily available at the common stores, although 60w, 50w and 20-50 weight is. Weird.

[xlr8nflorida]

Use high mileage mobil 10W-30.

[todesengel]

I use amsoil

[tomcat]

I use amsoil

I also use Amsoil 10W-40W. Notice the oil take longer to temp up.

Manfred E...........:saluting:
91 #906

[ZR-1nce removed]

Amsoil has a high zinc 10w40 that alot of us use. I'm sure your local performance shop can order it for you.

[Hammer]

I'm switching to the Valvoline VR1 racing oil, 10-30, for the next oil change. Real high in zinc and phosphorus and Marc Haibeck said it would work well for our motors.

[Z Factor]

The is a link to a thread/poll which has the various oils most of us use.

http://www.zr1.net/forum/showthread.php?t=3039

Here is a related thread/poll on oil filters.

http://www.zr1.net/forum/showthread.php?t=2476

Personally I go with Mobil 1 for both.

:cheers:

[tomtom72]

I also use Amsoil 10W-40W. Notice the oil take longer to temp up.

Manfred E...........:saluting:
91 #906

I noticed that also vs M1 10w-30, and when it's 'up to temp' the temp is a tad higher than the M1. But if I flog it thru the twisties it doesn't seem to end up at as high a reading as the 10-30 M1. If I flogged the car with the M1 for say 30 minutes the gauge would be 1/2 way, with the Amsoil it doesn't get quite to the 1/2 point. Seemed strange to me.

I did some reading over at the oil guy's site. Jim from FLA posted a link awhile back and I read the whole thing front to back. I think I'm going back to 10w-30 full synthetic.

:cheers:
Tom

[xlr8nflorida]

I can't find that technical document I posted but its around somewhere.

The jist of the article was that Mobil 1 High Mileage was fine for the LT-5 engine.

There are disadvantages to adding zinc if not done properly. I'm sure Valvoline and the others are good if you can find the 10W-30.

I go with what has worked for me. I have had several engines well over 100,000 that ran like a raped ape and they were clean as a whistle.
Mobil 1 works for me.

I buy it often for $19.99 to $25.00 for 5 quarts. I buy a ton of it for the 3 Corvettes and Mobil 1 has a rewards program.

I change my oil seasonal regardless of mileage. Many times I change it prematurely at 3,000 miles. If I get busy, then higher mileage.

On my Z - its really spoiled. Often times, it only has a few hundred miles on the oil. It gets seasonal changes, especially after the winter storage if I'm in a cold state. My oil cooler oil stays in good shape as a result. It is way overkill but my oil changes are dirt cheap since I always get the oil on sale and do it myself. If memory serves me right, regular mobil 1 is good for 6 months and extended mobil is good for 1 year. (as long as within mileage limitations)

I also do my coolant now at 1 year intervals.

[tomtom72]

:)

http://www.bobistheoilguy.com/cms/index.php?option=com_content&view=article&id=83

This is the start of that link you posted Jim. I just had to read it from the beginning. I don't remember which chapter you specifically linked, but I read that and then realized that there was more.

The only reservation that I have is that Bob sounds like he knows what he is talking about, and his flow vs viscosity vs psi stuff is a valid technical point....somehow I just can't bring myself to use a 5w- 30 or a 0w- 30 oil .... but like he says at the beginning chapter, forget what you think you know about motor oils. I find that after reading all of it that yes I held the common misconceptions because I grew up with natural base stock oils. Synthetics do not behave at all like natural base stock oils.

:cheers:
Tom

[WARP TEN]

Just noticed this thread. Here is a link to Marc Haibeck's oil evaluation and recommendation:

http://www.zr1specialist.com/HAT%20Web/articles/Modern%20Motor%20Oil%20and%20the%20LT5%20Engine.pd f

[scottfab]

I use Penzoil Ultra Synthetic.
It's cleaning agents stopped the lifter ticking I had.

http://www.pennzoil.com/motor-oil/pennzoil-ultra-synthetic-oil/

[Harvie]

Try Joe Gibbs they currently have the very best racing oil produced in USA today. I switched from RedLine 3 years ago and never looked back. I run 0-5 or 0-20 in Wash DC area in spring thru fall.

I run it in my 1200 HP street cars and use it in the Alky 2500HP to Nitro 5000HP big motors