Hi guys, just joined here. I've done a lot of searching and reading and there is a lot of really good info here, but I still have a question. I have a '96 Dodge Ram with a modified 12 Valve Cummins. The engine has a mild performance flat tappet cam and heavier valve springs. I'm looking for an off the shelf oil that will protect the flat tappet cam. What is the generally accepted minimum level of zinc and phosphorus in PPM that will keep the cam alive?
Oil for flat tappet Cummins
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Welcome fellow New Yorker!
The CJ-4 oils should be fine. I prefer synthetic.
Mobil 1 TDT 5w-40
Delvac 1 5w-40
Rotella T6
Delo 5w-40
Do want maximum protection? Order Mobil Delvac SHC from your local XOM distributor.
https://www.exxonmobil.com/Lubes/business_distributor.aspx
http://www.lindberg-lund.com/files/Tekniske datablad/EXXON-DELVACSHC-TD.pdf
The CJ-4 oils should be fine. I prefer synthetic.
Mobil 1 TDT 5w-40
Delvac 1 5w-40
Rotella T6
Delo 5w-40
Do want maximum protection? Order Mobil Delvac SHC from your local XOM distributor.
https://www.exxonmobil.com/Lubes/business_distributor.aspx
http://www.lindberg-lund.com/files/Tekniske datablad/EXXON-DELVACSHC-TD.pdf
Is the Cummins 6BT bad about Camshaft/Tappet wear in the first place?? I use to have 2 '97 12-Valve trucks both had exhaust brake springs, CJ-4 oil didn't cause any issues with mine nor have I seen camshaft/tappet failures on customers trucks....Keep in mind the latest 24-Valve ISB 6.7L's still use a Flat Tappet Camshaft! Put heavier springs on those Doubles the load on the Tappet compared to a 12-Valve.
Your performance cam is tiny compared too a Big Block Chevy RV Cam much less compare it to any Gasoline Performance Grind.
Your performance cam is tiny compared too a Big Block Chevy RV Cam much less compare it to any Gasoline Performance Grind.
Even some CJ-4 oils have some real good levels of zinc and moly in them. The Cummins ISX has been known for its cam lobe failures, but seems to be more about metallurgy than the oil.
Thanks for the replies. I have never heard of a cam failure in a 6B. I guess I'm just erring on the side of caution. I just rebuilt the engine about 2000 miles ago so I really don't want to break it. I would like to eventually switch to a synthetic, but I'm going to wait one more oil change before I do that just to make sure everything is broken in.
My engine has an aftermarket Hamilton Cam in it.(Generally regarded as the best you can buy for a Cummins). They recommend an oil additive to assure proper levels of zinc and phosphorus, but they can't tell me in PPM what those levels should be. (They're happy to sell me the additive though). I have run the additive for the initial break in and for the first oil change (which is still in the truck right now). The cam is by no means huge, .290"/.320" lift. The rocker ratio is 1.7 and the engine also has just slightly heavier valve springs. I also installed 1.3" face diameter tappets in place of the factory 1.1" diameter.
In my own bit of research, I have heard what seems to be the magic number of 1100 PPM zinc and phosphorus for a flat tappet cam to be happy. Can anyone confirm or deny that? I did call technical assistance and Shell, Chevron, and Mobil to ask about their oils. Shell Rotella T triple protection has 1200 PPM zinc and 1100 PPM phosphorus. Chevron Delo 400 LE has 1300 PPM zinc and 1200 PPM phosphorus. The guy at Chevron also told me that cam failures are not caused by low levels of ZDDP. He said they are caused by [censored] overseas manufactured camshafts and that it was just a coincidence that the [censored] cams were started to be manufactured at the same time ZDDP levels were being lowered...hmmmm. The tech and Mobil was unable to tell me the levels in their Delvac oil since it was proprietary.
Anyway, I picked up the Delo 400 LE. It will be going in the truck this afternoon. I plan to run it for 4-5000 miles then switch to a synthetic.
If anyone has any suggestions or other input, I'd love to hear it!
My engine has an aftermarket Hamilton Cam in it.(Generally regarded as the best you can buy for a Cummins). They recommend an oil additive to assure proper levels of zinc and phosphorus, but they can't tell me in PPM what those levels should be. (They're happy to sell me the additive though). I have run the additive for the initial break in and for the first oil change (which is still in the truck right now). The cam is by no means huge, .290"/.320" lift. The rocker ratio is 1.7 and the engine also has just slightly heavier valve springs. I also installed 1.3" face diameter tappets in place of the factory 1.1" diameter.
In my own bit of research, I have heard what seems to be the magic number of 1100 PPM zinc and phosphorus for a flat tappet cam to be happy. Can anyone confirm or deny that? I did call technical assistance and Shell, Chevron, and Mobil to ask about their oils. Shell Rotella T triple protection has 1200 PPM zinc and 1100 PPM phosphorus. Chevron Delo 400 LE has 1300 PPM zinc and 1200 PPM phosphorus. The guy at Chevron also told me that cam failures are not caused by low levels of ZDDP. He said they are caused by [censored] overseas manufactured camshafts and that it was just a coincidence that the [censored] cams were started to be manufactured at the same time ZDDP levels were being lowered...hmmmm. The tech and Mobil was unable to tell me the levels in their Delvac oil since it was proprietary.
Anyway, I picked up the Delo 400 LE. It will be going in the truck this afternoon. I plan to run it for 4-5000 miles then switch to a synthetic.
If anyone has any suggestions or other input, I'd love to hear it!
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CJ4-spec'd HDEO's all seem to have about 1200 ppm of Phosphorous. CI4+ oils did have about 1400ppm, but that was 9 years ago. If you can find Valvoline Premium Blue Classic or Mobil Delvac MX, they might still have the higher level of ZDDP. These are both conventional 15w40's, though. I don't know of any 5w40 HDEO's that would have over 1200 ppm of Phos. Maybe Joe Gibbs Driven? Redline 5w40 may, but it's not really an HDEO, and it's expensive. Maybe AMSoil AMO 10w40 has high ZDDP. Otherwise, you could buy readily available 5w40 CJ4 HDEO's and raise their zddp level with ZDDPlus or Redline oil additive.
Cummins did have a round of flat tappet wear problems on their B & C-series engines about 20 years ago. They got over it by improving the metallurgy of the lifters.
Since Hamilton is recommending a zddp additive, I would respect that. The increase in lift and valve spring load may sound small, but that doesn't tell the whole story on cam contact stress. If the radius of curvature over the nose of the cam is small, you could be running very high contact stresses. Only the cam manufacturer would know that kind of information. The combination of higher spring loads, small cam radius at peak lift, and continuous operation below 2000 rpm (as you would have in a diesel) is a good recipe for cam wear.
Cummins did have a round of flat tappet wear problems on their B & C-series engines about 20 years ago. They got over it by improving the metallurgy of the lifters.
Since Hamilton is recommending a zddp additive, I would respect that. The increase in lift and valve spring load may sound small, but that doesn't tell the whole story on cam contact stress. If the radius of curvature over the nose of the cam is small, you could be running very high contact stresses. Only the cam manufacturer would know that kind of information. The combination of higher spring loads, small cam radius at peak lift, and continuous operation below 2000 rpm (as you would have in a diesel) is a good recipe for cam wear.
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The Delvac SHC that I mentioned previously has P 1300 Zn 1500. It's intended specifically for high performance diesel applications and extended oil change intervals. It's available from XOM distributors.
Hamilton can't give me an exact answer which is kind of annoying. They can't tell me in PPM what I should be shooting for and just tell me that an additive is "a good idea." I was hoping for something more definitive than that. I do know that there is such a thing as too much though...
Well, I just changed the oil in the truck to the Delo 400 and now I'm afraid to drive it until I find an additive. Where I'm going to find that on a Friday and somewhat local I have no idea. Ugh.
Well, I just changed the oil in the truck to the Delo 400 and now I'm afraid to drive it until I find an additive. Where I'm going to find that on a Friday and somewhat local I have no idea. Ugh.
Contact user m37charlie about the Mobil SHC.
You might be able to find the Red Line addative locally, or have it shipped quickly enough if you've got Amazon Prime.
http://www.redlineoil.com/product.aspx?pid=121&pcid=21
http://www.redlineoil.com/dealers.aspx
You might be able to find the Red Line addative locally, or have it shipped quickly enough if you've got Amazon Prime.
http://www.redlineoil.com/product.aspx?pid=121&pcid=21
http://www.redlineoil.com/dealers.aspx
Does anyone know if there is an additive that is on the shelf at most parts stores that will get me by? I tried looking for ZDDP Plus, but I can only find it online. It won't be here 'til next week and I need to drive my truck before that. I've heard that STP or GM EOS might be viable options. Yes, no, maybe?
Sorry to be so post-happy here, but I think I may have found something. The local Napa carries Lucas TB Zinc Plus. I googled it and I think it's a viable option. Anyone use it?
Why do you want to go to a syn oil. If you thought it was better why didn't you just put it in right away. The car manufacturers put it in from the factory. There have been more miles put on Cummings motors every year with dino oil than syn on the road with no difference in failures.
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