High mileage oil recommendations?

[scurvy]

Ah, memories. My parents handed me a set of keys to their 1979 3/4 ton Plymouth Voyager van when I was 16, back in the mid-90s. Beautiful three-tone paint job (light blue, royal blue & rust) with the same 360 CID V8 under the doghouse and the venerable A727 Torqueflite. Best I ever saw was 12 mpg, typically around 10 and could be as low as 7 in the winter.

My Dad chuckled and said, "Hope you like changing spark plugs..." and about every 3 weeks I had to remove the front two from the passenger side as they would foul out... about 175k miles on it then. You know, the two hardest to reach plugs? Eventually had the engine & carb rebuilt at about 230k miles and it ran well for the next 15 years until my Dad sold it a few years ago with over 300k on it.

FWIW, in the piedmont of northwest Georgia, we used Castrol GTX 20w50 and Fram filters exclusively for the van. The guys rebuilding it said the pistons, cylinder bores & bottom end looked amazingly good considering the years & miles on it.

 

[Cubey]

Originally Posted By: Clevy
OP
Be thankful that gas guzzling 360 has a 2 barrel carb. I bet its already painful to fill the gas tank,imagine how many less miles you would get per tank once you double the air and fuel. Likely helps prevent fuel diluted oil as well.
Sir. Try a few different oils out. See which the engine runs best with. I'm sure you will know every little sound that motor home makes and you will be able to hear it talk to you once you get some miles on er.
Keep us informed of your observations if you don't mind.


Hmm... my understanding was that mpg would benefit from 4bbl. I'm no expert on carburetors though. I did entertain the idea of changing go 4bbl but the cost to change over (since I wouldn't wanna change the intake manifold myself) was too great to bother. I think the theory was that if the engine has to work less hard, it would use less fuel.

 

[Cubey]

Originally Posted By: scurvy
...with the same 360 CID V8 under the doghouse and the venerable A727 Torqueflite. Best I ever saw was 12 mpg, typically around 10 and could be as low as 7 in the winter.

My Dad chuckled and said, "Hope you like changing spark plugs..." and about every 3 weeks I had to remove the front two from the passenger side as they would foul out... about 175k miles on it then. You know, the two hardest to reach plugs? Eventually had the engine & carb rebuilt at about 230k miles and it ran well for the next 15 years until my Dad sold it a few years ago with over 300k on it.


A727 velernable? How so? From what I have heard it's generally a very tough transmission. Although, the previous, previous owner** had the transmission rebuilt in 2011. However, I don't know the real mileage. A 1991 oil change sticker on the door states 90,xxx miles. Unless it has only been driven about 45k miles in the last 22 years, it may be at 235k. But I digress.

The A727 is #3 in this top 5 list of tough automatic transmissions good for offroad use (gotta scroll down past the manual transmissions)...
http://www.4x4review.com/Features/Tech/Top10Transmissions/tabid/135/Default.aspx

To quote the page:
Quote:
The A727 was available in two primary options; the standard model, typically found in large rear wheel drive cars, and the heavy-duty model which was typically found in their larger 1/2, 3/4 and 1+ ton trucks (both 2 and 4wheel drive models). The A727 HD was, and still is, sought after by drag racers and monster truck racers because of its vast controllability and tremendous strength - the A727 can quite easily soak up 500+ horsepower and 400 lb./ft. of torque with just a few simple modifications. The TorqueFlite 727 was such a popular slushbox that it was used by other manufacturers around the world, such as Range Rover, AMC, and Monteverdi.


The spark plugs are all easy to get to in my van so I'm not sure what you are talking about. Remove the doghouse cover and they're all right there, 4 on each side. It almost takes longer to remove and install the doghouse cover off than it takes to replace the spark plugs. Having replaced all 8 last year with new NGKs, I know.


(**Guy I bought it from, he bought it and never registered it.. and stated he had a suspended license for DUI)

 

[salv]

He said venerable, not vulnerable. It was a compliment.

 

[Cubey]

Oops!

Take note of the time in which I posted that reply. I was tired. Hence the horrible spelling of "vulnerable" and the misunderstanding. I saw the word but misread it and went on to combine the spellings of the two words... haha.

Oh and one other thing I meant to say in that post is who knows what kind of treatment the old transmission got that lead to it's apparent failure and rebuilding. Lack of fluid and filter changes perhaps. It's all just speculation though since I don't know.

 

[Maxima97]

Maxlife 10W40 or 10W30 will do. It is a Syn-blend with 168ppm of moly and seal conditioner. 3.3 HTHS is good for towing. TBN8.3 is enough for 5k-7.5k OCI. 1st in the market during early 2000. The others are the followers.

 

[Clevy]

I've never in my life seen a 4 barrel carb on any engine be easier on fuel that a 2 barrel. In fact I had a 350 in a truck that had a 2 barrel and it would routinely get 24 mpg highway. That exact engine went into my cutlass and I put the 4 barrel intake and q-jet onto it and I was in heaven if it saw 17mpg.
I'm not saying its not possible but in my experience very unlikely.
Anyways it's neither here nor there. It sounds like you have a great unit there. All the high mileage oils available are decent and will do well in your truck. I'd try a different oil at each change until one stands out as superior.
Have a great time travelling. I'm about 20 years away from that point but counting the days

 

[motorguy222]

Originally Posted By: Maxima97
Maxlife 10W40 or 10W30 will do. It is a Syn-blend with 168ppm of moly and seal conditioner. 3.3 HTHS is good for towing. TBN8.3 is enough for 5k-7.5k OCI. 1st in the market during early 2000. The others are the followers.


Maxlife has been changed and the PDS doesnt list moly as an additive.It has also been thinned and is now "Energy Conserving".It now has a TBN of 8.8 and the HTHS has more than likely changed to a lower rating,as has others that meet the SN Energy Conserving standard.

It seems to be a good oil.

I have used Mobil Super High Mileage and it seemed to work well,it a syn blend too.

Maxlife

 

[steve20]

Jeeezzz Cubey sorry to hear about your issues with the vehicle. But for 1400 bucks, I think you got a good deal.
Maxlife 10-40 sounds like a great choice


4V carbs can give higher gas mileage if you stay out of the secondaries.
With 4V you get 2 smaller primaries to do the daily driving---they are smaller than the 2V you would be using all the time