Which oil should I use for 78 Dodge Custom 150 ?

[OldDodgeJohn]

Hey I recently bought a 1978 Dodge Custom 150. The original 318 has 135K miles. I am excited to begin taking care of this old girl. She was in the same family since new, grand-dad-son. It seems the body was well taken care of, not sure about the engine, when I asked the owner what oil he has been using he just said whatever is on sale.

So anyway for several years now I have heard great things about Shell Rotella, even used it in motorcycles. Would it be wise to use the Rotella in this old engine. I am not sure about the consumption since I haven't owned it but a couple of weeks. Thoughts?

 

[jk_636]

Perhaps a Pennzoil conventional or Valvoline with Riselone or MMO? Thats where I would start. I have heard of people running Rotella in older harleys as well (panheads, shovelheads etc.) Im not sure how well it would work for you in this instance though.

 

[datech]

So, are you going to use this everyday, or just once in a while?

OUt on the highway, or just around town?

 

[05LGTLtd]

I'd wager Rotella T5 would be fine choice...

 

[OldDodgeJohn]

Probably just every now and then. Definitely a 2nd vehicle. I just bought it cause everyone needs a truck for those runs to Home Depot, etc. So not many miles per week, say 100 to 150.

 

[Skid]

Most oils won't cut it in this case.

An American V8 of the 1978 vintage = flat tappets, stiff valve springs, heavy valves, leverage on the rocker arms... and the corresponding need for heavy doses of ZDDP. Probably, the only commonly available oil with enough ZDDP is Castrol Edge Syntec 5W-50. Other oils might work, but they're not intended/marketed for it.

 

[OVERKILL]

Originally Posted By: Skid
Most oils won't cut it in this case.

An American V8 of the 1978 vintage = flat tappets, stiff valve springs, heavy valves, leverage on the rocker arms... and the corresponding need for heavy doses of ZDDP. Probably, the only commonly available oil with enough ZDDP is Castrol Edge Syntec 5W-50. Other oils might work, but they're not intended/marketed for it.



No. They had weak valve springs, about the only engines with relatively heavy springs would be hi-po engines from the late 60's like the BOSS 302, 351C, GM's 302, 327....etc. Stuff that rev'd.

A 302/351 from the late 80's in an F-150 probably has heavier springs than that old Dodge and they were flat tappet too.

Heck, we ran (and broke in) a Lunati Voodoo in an SBC with relatively heavy springs (enough that she didn't float at 6,500) on plain-Jane Kendall 15w40 and when it was swapped out a few years later for a roller setup the cam and lifters looked mint.

 

[Ramblejam]

Originally Posted By: Skid
Most oils won't cut it in this case.

An American V8 of the 1978 vintage = flat tappets, stiff valve springs, heavy valves, leverage on the rocker arms... and the corresponding need for heavy doses of ZDDP. Probably, the only commonly available oil with enough ZDDP is Castrol Edge Syntec 5W-50. Other oils might work, but they're not intended/marketed for it.


We're discussing a '78 Dodge pickup with an original 318, and you're recommending oil that retails for over $9/quart?

Originally Posted By: OldDodgeJohn
Thoughts?


Welcome to the forum, and congrats on the new truck! You'll have many recommendations soon coming your way...

 

[dave1251]

I would not look for some boutique brew for a stock V8 from 1978 with a such a mild tune of around 160HP and 255LBS of torque. QS Defy or your option of Rotella 10W30 and you will be good to go.

 

[Skid]

Originally Posted By: OVERKILL
Originally Posted By: Skid
Most oils won't cut it in this case.

An American V8 of the 1978 vintage = flat tappets, stiff valve springs, heavy valves, leverage on the rocker arms... and the corresponding need for heavy doses of ZDDP. Probably, the only commonly available oil with enough ZDDP is Castrol Edge Syntec 5W-50. Other oils might work, but they're not intended/marketed for it.



No. They had weak valve springs, about the only engines with relatively heavy springs would be hi-po engines from the late 60's like the BOSS 302, 351C, GM's 302, 327....etc. Stuff that rev'd.

A 302/351 from the late 80's in an F-150 probably has heavier springs than that old Dodge and they were flat tappet too.

Heck, we ran (and broke in) a Lunati Voodoo in an SBC with relatively heavy springs (enough that she didn't float at 6,500) on plain-Jane Kendall 15w40 and when it was swapped out a few years later for a roller setup the cam and lifters looked mint.


I guess it's all in context. I'm comparing it to, say, a DOHC flat tappet setup. The difference in spring rate is pretty dramatic. In addition, you have the leverage of the rocker working against you at the tappet/cam. Splash lube. Also keep in mind that if you're just putting around, it's harder on the cam/tappet than if you're revving.

At any rate, I wouldn't recommend anything but a high ZDDP oil for an old V8 to someone else. But, what someone wants to do with their own car is their choice.

 

[GumbyJarvis]

Valvoline Maxlife, Quaker State High Mileage, Peak Conventional, Pennzoil High Mileage or Semi Syn

10w40...

I wouldn't even hesitate to try Motorcraft 15w40 either.

 

[SilverC6]

I like your choice of the T5 Rotella 10w30 semi-synthetic.

 

[GumbyJarvis]

that being whatever is cheaper out of the above reccomendations

 

[mrsilv04]

Rotella T 10w30. Around $13 a gallon. Excellent for an older engine.

 

[Kuato]

Originally Posted By: OldDodgeJohn
Hey I recently bought a 1978 Dodge Custom 150. The original 318 has 135K miles. I am excited to begin taking care of this old girl. She was in the same family since new, grand-dad-son. It seems the body was well taken care of, not sure about the engine, when I asked the owner what oil he has been using he just said whatever is on sale.

So anyway for several years now I have heard great things about Shell Rotella, even used it in motorcycles. Would it be wise to use the Rotella in this old engine. I am not sure about the consumption since I haven't owned it but a couple of weeks. Thoughts?


You asked about Rotella, and the 5w40 synthetic would be a great choice for this engine IMO. 10w40 was specified in the 70s, and the T6 has a good bit of zddp so no worries with the flat tappets.

Those old 318s can go a long long time, but you may need a water pump and alternator every 100k.

 

[marc1]

Originally Posted By: OldDodgeJohn
...when I asked the owner what oil he has been using he just said whatever is on sale.


This is the best answer.

 

[zrxkawboy]

Originally Posted By: 05LGTLtd
I'd wager Rotella T5 would be fine choice...


I agree with this. That said, any quality 10W30 will work just fine. If the seals/gaskets seep a bit, a High Mileage oil might be a good choice.

 

[toneydoc]

Hello and welcome

Hope the truck lasts you many more years. And should give you plenty more miles.

Since winter is coming and you live down here in the south where it doesnot get too cold, Rotella T is a great choice or probably any 5w30 or 10w30 that is a good quality oil will serve you fine. And skip out on any additives. That motor will do fine without them.

 

[DoubleWasp]

Flat tappet engine, you're much better off with Rotella. Not all cams are created equal, and this engine has some miles behind it. Treat it well.

 

[Dallas69]

I had a 1979 Chrysler 360 v-8 up until a few years ago and allI used was either Pennzoil Conventional or Quaker State 10w30 and had no issues at all
You dont need anything too fancy or expensive