Oil for '92 7.3L Ford

[RWEST]

My brother's church just picked up a '92 Ford 15 passenger van. The thing's in great shape, for 15+ years/150K miles and runs well. It has the 7.3L (IH, I think) diesel.

I don't know about its previous oil history.

Whattya' think - Rotella 10-30 or 5-40, or whichever is available? Or, do we worry too much about minor details?

 

[addyguy]

Cheap 10w30 or 15w40 HDEO for a couple of runs to guage what consumption is, and maybe clean out deposits, if any, from previous regime. Then base oil chaoice on expected service and expected temperatures.....

 

[Doug Hillary]

Hi,
if it has the DT466 IH engine you are lucky - they are very durable engines! Their history goes back many decades

A 15w40 HDEO such as Delvac 1300 will do the job according to operating ambient requirements of course. A 5W-40 synthetic such as Rotella T or Delvac 1 will be excellent choices too

 

[OVERKILL]

Originally Posted By: Doug Hillary
Hi,
if it has the DT466 IH engine you are lucky - they are very durable engines! Their history goes back many decades

A 15w40 HDEO such as Delvac 1300 will do the job according to operating ambient requirements of course. A 5W-40 synthetic such as Rotella T or Delvac 1 will be excellent choices too


Doug: It would be the DT444.

 

[Doug Hillary]

Hi,
OVERK1LL - Thanks!

 

[OVERKILL]

No prob Doug

 

[Jim Allen]

With a '92 it's the naturally aspirated "D" 444 7.3L, the turbo "DT" 444 IDI, the turbocharged engine not having debuted yet ('93-94 only).

If it's in PA and will be used in the winter, especially if it won't be plugged in for starting (but it should be), either 5W40 syn or 10W30, depending on budget. If the driver is religious about plugging it in for cold starts, I believe you can get by with a 15W40 on a cold start. I have a similar 6.9L engine and it does just fine on 10W30 and if you look at the viscosity chart for a climate like PA, that's the recommended viscosity. I can only imagine how a church bus will be used, but I can't help but think it will be a lot of cold start, short hop type driving, with lots of time sitting in the churchyard. For that, maybe a 10W30 is the best choice.

On the other side, the aforementioned scenario combined with lots of idling and a tired fuel system might result in a "slobbering" engine that will suffer from fuel dilution resulting in viscosity loss. In that case, the heavier viscosity might be the better choice

 

[bullwinkle]

I'm personally a big fan of the Rotella T conventional 15w40, if your batteries are good, and you plug it in when it gets REALLY cold (like below 20 F), you'll be happy with it.

 

[1040 WreckerMan]

The IH IDI's, both the 6.9 and the 7.3, are fairly easy on oil. One thing that you do need is an oil that will handle high soot loading as the IDI's are prechamber type engines and are fairly "dirty".

What oil weight would depend I think on how this van is going to be used. Since it's a church van I'm guessing lots of cold starts and short trips? If that is the case a good diesel rated 10w30 would be fine. Otherwise a 40wt, whether it be 5 or 15w might be a good idea. 5w40 if you can't leave the block heater plugged in, 15w40 if you can.

The 15w40 is probably going to be the most economical choice and easiest to find.