Best oil for an 85 720

[85 720 king cab 4x2]

What’s the best oil running an 85, 720??

[datzenmike]

10w30

 

I use Shell Rotella T4 for the higher zinc content.

[85 720 king cab 4x2]

Hey thanks a million , I ve got another question for you I was kinda hoping you were going to answer.

[85 720 king cab 4x2]

I just recently discovered fuel in my oil! I’ve been reading that short trips is one of the causes for this. As to I am guilty of this ,my job is only a couple miles from my house and Besides that morning across the bridge a few more miles in the grocery store and basically around town in a very small town on the coast in  Oregon is about all the real mileage my 720 gets , I recently bought a locking gas cap a couple months ago! Could this be another reason why there could be fuel in my engine Oil?.

[85 720 king cab 4x2]

With gas prices the way they have been is the reason for the locking gas cap, there is always the threat of someone coming by and siphoning my gas too I’m beginning to think this was a bad idea. I should of probably found out a way to be able to lock the fuel door?. Could I be rigt?

[85 720 king cab 4x2]

I guess I will check back in a bit to see if datsunmike has some answers for me or anyone else in the group ! It’s starting to worry that I may have done damage to my engine! Oh I was going to add the fact that also have a weber carburetor on my 720 with a manual choke, and have had problems with my fuel pump so insted of rumming it through the relay under the dash on he Drivers side I’ve run a seprate line and attachéd it to my ignition fuse the first one on the left , so when I turn on and start her up it kicks on and then when I turn off the engine it turns off as well. Could there be too much fuel running?

[datzenmike]

The choke is on longer in the winter and with short trips it basically on all the time. The choke forces a rich condition to help make it easier to drive when cold. It wouldn't be unreasonable to smell it in the oil. Let warm up for three minutes first. Truck will spend more time warmed up. The heat from a normal amount of driving will dry gas out of the oil. A block heater is also great for shortening the warm up. Put on a timer a hour and a half before you need to go. I find when you start the engine the needle on the gauge is already reading.

 

Maybe change the oil more often

[85 720 king cab 4x2]

Since I am a newbie I should of started a differnt topic! Sorry if I can figure out how to do this is going to “ Fuel  in my Oil” but I am not real great with computers so I hope someone could help me with where do i or do I need to start a new topic??

[85 720 king cab 4x2]

Ok so I may be a dumd Ass but what a Block Heater ? Well that makes me feel a little bit better but I don’t know why but it worries me still! I’ve changed the oil 3 times since I’ve had the 720 and have only put like 800-900 miles on it. And thanks you for all of your help or ideas on my cheesy topic.

Edited February 27, 2023 by 85 720 king cab 4x2
. Forgot info?

[datzenmike]

On carburetor engines starting and warm uo require that a choke be used. This is a restriction that forces the engine to suck in more fuel for a richer mix. Cold engines don't evaporate the fuel properly so adding more helps it run smoother and with more power during the warm up period. Naturally not all the fuel can be burned and much of it will work it's way down past the rings and mix with the oil. Normally, running at full temperature will heat the oil and evaporate away any fuel. Continued cold weather short trips will accumulate fuel in the oil. Lengthen the time the engine is fully warmed up. Let sit in driveway for 3-5 minutes before driving and add a little more time driving to and from work will help. Perhaps just go for a drive on the weekends.

 

Block heater is just like the name implies. It's a plug in heater.

 

 

 

 

This one, above replaces one of the core plugs. This one below connects in line with your heater hose.

 

[85 720 king cab 4x2]

Hey Thanks-A-Million ! I do appreciate your advice and help! I think I will also try one of these her you have shown me.I was so worried I blew a head gasket, and am really New to this group and am forever grateful for your and everyone’s help it didn’t take long to start me into doing everything I can to keep this truck rolling if you could’ve seen it before I got it I think I might have a before picture. This is about how far I’ve gotten. I’ll try to post a picture..Thanks again to DatsunMike for all your advice!!

[85 720 king cab 4x2]

Well I can’t figure out how to post a pic when I did it told me the photo was too large??see what I mean by being a newbie!! I don’t know maybe somehow I figured out. Thanks again.

[85 720 king cab 4x2]

T4 10w-30 for gasoline engines (shell)

[85 720 king cab 4x2]

It says Rotella T4 10w-30: this. Is for Diesel engines?.

[620slodat]

A diesel oil will have more zinc in it. Zinc will help with diesel motors and older flat tappet motors.

 

Don

[datzenmike]

8 hours ago, 85 720 king cab 4x2 said:

It says Rotella T4 10w-30: this. Is for Diesel engines?.

 

Yes it's for diesels and still for the foreseeable future still retains the old ZDDP levels that oils 30 years ago had. T4 is 1,200 PPM ZDDP but gasoline engine oils makers have been phasing it out as it's not good for catalytic converters and new engines don't need this protection. Today's oils are around 600-700 PPM and though the makers say they are reverse compatible with older engines I'm not so trusting with my valuable valve train. The design of out old rocker on cam need a good percentage of anyi scuff ZDDP. 

 

As getting this level is as simple as walking down the aisle to the diesel oil section, why not?

 

Diesel oil is very detergent compared to gas engine oil so you may notice it darkens very fast after a change. This is the oil removing built up crap on the engine's insides. I noticed this for the first few oil changes. The oil is still good but change every 5k and always put a new NAPA WIX oil filter on at the same time. I've been using T4 for 10 years though I don't drive a lot of miles, hardly any, so I change it every two years and that's well below the 5k change interval. That reminds me this is oil change year.

[Thomas Perkins]

Jed says oil is oil...

 

[85 720 king cab 4x2]

Ok, I still appreciate the help, and it  4 3/8 with a new filter correct? If u would like to talk about any aspect of the construction business this is a complete different story! This forum Is why I am here because I don’t know trucks or the Automobile business and could use all the help I an get there’s always money  going into this Truck and I can’t afford to waste $$ on not knowing something that may fuck-up what I am trying to make better! Isn’t this why we have these sorts of things! ☮️!

[datzenmike]

It takes whatever it takes to end up at the full line. Half fill the oil filter before quickly spinning it on and be sure to check the old rubber seal didn't stick to the block and wet the new one with oil so it comes off easier next change. After running check level one last time.

[85 720 king cab 4x2]

right-on I plannned  on some of that ! Just looking like a dumbass and checking! Thx!

[datzenmike]

The recommended fill amount is just so you buy enough. Left overs are for topping up.

[Stoffregen Motorsports]

Hey @datzenmike. Let me pick your brain.

 

Warning - THREAD JACK IN PROGRESS!!!

 

I recently started using the factory installed block heater in my Dodge Cummins. Never needed it, but we're having a helluva winter...

 

Question is, is this introducing electromagnetic current to my cooling system, with potential electrolysis issues? It's something I have been thinking about since I started using the block heater.

[datzenmike]

Perhaps if the truck were grounded to the electrical grid. Same as you being insulated and touching a live wire there's no flow of current. If the block heater has a ground it grounds the exterior of the heater so any 'flow' would be localized to the heater itself.

 

Block heaters used to be very common with carburetor vehicles. EFI??? hardly ever. I don't remember there being problems with electrolysis

[Stoffregen Motorsports]

That makes sense.

 

These Cummins powered Rams are cold blooded beasts. If running uphill, no problem, but when running downhill, it's all I can do to keep heat in it. It's a pretty common issue, and I'm ready to try the old cardboard across half the grille trick.

[Thomas Perkins]

15 hours ago, datzenmike said:

It takes whatever it takes to end up at the full line. Half fill the oil filter before quickly spinning it on and be sure to check the old rubber seal didn't stick to the block and wet the new one with oil so it comes off easier next change. After running check level one last time.

Never ever heard that before Mike.Putting oil in the filter before installing.