15W-40 okay for 460 Ford?

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Recently bought a 1989 Econoline RV with a 460 in it. Only 72k miles on it, should I use 15W-40 in it for higher zinc as this is a flat tappet engine I assume? Figure it would appreciate the thicker oil due to the heavy weight of the vehicle and possible towing a car/or ATV trailer behind it occasionally on trips, heat of summer and what not or would 10W-30 be fine? I have a lot of Rotella leftover from my 7.3 diesle that I sold that needs used up anyway! Just wanna make sure this is okay for the engine as I don't know much about them.
 
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Originally Posted by jongies3
Recently bought a 1989 Econoline RV with a 460 in it. Only 72k miles on it, should I use 15W-40 in it for higher zinc as this is a flat tappet engine I assume? Figure it would appreciate the thicker oil due to the heavy weight of the vehicle and possible towing a car/or ATV trailer behind it occasionally on trips, heat of summer and what not or would 10W-30 be fine? I have a lot of Rotella leftover from my 7.3 diesle that I sold that needs used up anyway! Just wanna make sure this is okay for the engine as I don't know much about them.
Yes, if it has flat tappets, 15W-40 is the way to go -- not because of the ZDDP but because you need a thick base oil. A typical 15W-40 has almost twice the base-oil viscosity of a 5W-30, which is what you need to protect the flat tappets. You don't need high ZDDP. Besides, most of the latest 15W-40 oils don't have high ZDDP. The only concern is if you can start with 15W-40 in the winter in Montana. See my base-oil viscosity (HTFSV) tables posted in the white-papers section for more details.
 

jongies3

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Originally Posted by Gokhan
Originally Posted by jongies3
Recently bought a 1989 Econoline RV with a 460 in it. Only 72k miles on it, should I use 15W-40 in it for higher zinc as this is a flat tappet engine I assume? Figure it would appreciate the thicker oil due to the heavy weight of the vehicle and possible towing a car/or ATV trailer behind it occasionally on trips, heat of summer and what not or would 10W-30 be fine? I have a lot of Rotella leftover from my 7.3 diesle that I sold that needs used up anyway! Just wanna make sure this is okay for the engine as I don't know much about them.
Yes, if it has flat tappets, 15W-40 is the way to go -- not because of the ZDDP but because you need a thick base oil. A typical 15W-40 has almost twice the base-oil viscosity of a 5W-30, which is what you need to protect the flat tappets. You don't need high ZDDP. Besides, most of the latest 15W-40 oils don't have high ZDDP. The only concern is if you can start with 15W-40 in the winter in Montana. See my base-oil viscosity (HTFSV) tables posted in the white-papers section for more details.
I'm not worried about cold since the RV probably won't get moved much in winter. Has a block heater though if need be!
 

jongies3

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Originally Posted by JLTD
Sounds like a great choice for that big block. Any chance you'll do a UOA?
Perhaps! I just sent off a 10k uoa of the Mobil 1 in my Tacoma. It'll be my first uoa experience actually.
 
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Cincinnati, OH, USA
Originally Posted by jongies3
Originally Posted by Gokhan
Originally Posted by jongies3
Recently bought a 1989 Econoline RV with a 460 in it. Only 72k miles on it, should I use 15W-40 in it for higher zinc as this is a flat tappet engine I assume? Figure it would appreciate the thicker oil due to the heavy weight of the vehicle and possible towing a car/or ATV trailer behind it occasionally on trips, heat of summer and what not or would 10W-30 be fine? I have a lot of Rotella leftover from my 7.3 diesle that I sold that needs used up anyway! Just wanna make sure this is okay for the engine as I don't know much about them.
Yes, if it has flat tappets, 15W-40 is the way to go -- not because of the ZDDP but because you need a thick base oil. A typical 15W-40 has almost twice the base-oil viscosity of a 5W-30, which is what you need to protect the flat tappets. You don't need high ZDDP. Besides, most of the latest 15W-40 oils don't have high ZDDP. The only concern is if you can start with 15W-40 in the winter in Montana. See my base-oil viscosity (HTFSV) tables posted in the white-papers section for more details.
I'm not worried about cold since the RV probably won't get moved much in winter. Has a block heater though if need be!
You could add a stick-on Wolverine oil pan heater & run them both together, it really helps in extreme cold, then you know you could start it anytime.
 
Originally Posted by Gokhan
Originally Posted by jongies3
Recently bought a 1989 Econoline RV with a 460 in it. Only 72k miles on it, should I use 15W-40 in it for higher zinc as this is a flat tappet engine I assume? Figure it would appreciate the thicker oil due to the heavy weight of the vehicle and possible towing a car/or ATV trailer behind it occasionally on trips, heat of summer and what not or would 10W-30 be fine? I have a lot of Rotella leftover from my 7.3 diesle that I sold that needs used up anyway! Just wanna make sure this is okay for the engine as I don't know much about them.
Yes, if it has flat tappets, 15W-40 is the way to go -- not because of the ZDDP but because you need a thick base oil. A typical 15W-40 has almost twice the base-oil viscosity of a 5W-30, which is what you need to protect the flat tappets. You don't need high ZDDP. Besides, most of the latest 15W-40 oils don't have high ZDDP. The only concern is if you can start with 15W-40 in the winter in Montana. See my base-oil viscosity (HTFSV) tables posted in the white-papers section for more details.
I've read your posts but still i find it hard to believe that really flat tappets don't require high ZDDP with modern oils, i've seen how for example modern Castrol GTX wiped out the cam in a friend's Triumph TR6, and it seems like Castrol GTX doesn't have more than 600-800ppm of Z&P these days. He now uses Valvoline VR1 20W-50 in it , which i recommended to him and the engine is running perfectly with a new cam and tappets.
 
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This engine is pretty understressed and makes surprisingly little power for its displacement, so it would likely be fine on the recommended oil. There will necessarily be some fuel economy penalty in using a 15W-40 over the recommended grade, although given that this rig won't be a fuel economy champ on any oil that won't be a difference you'll really feel. Having written the above, I do think that the 15W-40 would be a good choice for this rig. I'd use it without hesitation, particularly if I had some laying around, although if a thirty grade really isn't adequate then the damage has already been done in 72K of use.
 
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Originally Posted by FordCapriDriver
I've read your posts but still i find it hard to believe that really flat tappets don't require high ZDDP with modern oils, i've seen how for example modern Castrol GTX wiped out the cam in a friend's Triumph TR6, and it seems like Castrol GTX doesn't have more than 600-800ppm of Z&P these days. He now uses Valvoline VR1 20W-50 in it , which i recommended to him and the engine is running perfectly with a new cam and tappets.
His 460 is loafing along with a low stress valve train. Your friends TR6 is another story. My 26 year old flat tappet F150 has lived it's life (255K miles) on modern 5w and 10w-30 oil without any problems.
 
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Paramount, California
Originally Posted by FordCapriDriver
I've read your posts but still i find it hard to believe that really flat tappets don't require high ZDDP with modern oils, i've seen how for example modern Castrol GTX wiped out the cam in a friend's Triumph TR6, and it seems like Castrol GTX doesn't have more than 600-800ppm of Z&P these days. He now uses Valvoline VR1 20W-50 in it , which i recommended to him and the engine is running perfectly with a new cam and tappets.
Was that Castrol GTX 20W-50? If so, I don't see a problem. The problem with these anecdotes is that we don't know what really caused the failure. It could be that the cam was already failing and the VR1 20W-50 would make no difference. My point is that most modern oils with lower ZDDP levels offer more wear protection than most obsolete oils with higher ZDDP levels. Would a 1985 API SF oil would protect more wear protection than a modern oil? I don't think so. There is even some study: https://www.bobistheoilguy.com/foru...for-selected-sf-through-sn-oils-pcmo3-en
 
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Not sure what year Ford went to the relaxed rings, but my '91 F250 would eat oil like candy unless I ran a heavier weight. 15W 40 worked great in that truck - I think you'll be just fine running it...
 
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