6.9l l6

pcdreams · 03-09-2016, 02:06 PM

I'm looking at an 87 IH bus with a 6.9L L6 motor. What can you tell me good or bad about it?

If I'm seeing the right thing in my searches, it's not a turbo (likely too old for that)

Mostly I'm interested if it's a solid motor, and how it ranks compared to say a 444 or 466

I'm also wondering what type of transmission it has. I know it's an automatic.

The pic I've seen look like the body is solid. Just don't want to drive 4 hrs each way if the engine isn't a solid one. Only reason I'm considering it is price $1200.

crazycal · 03-09-2016, 03:02 PM

You need to provide more info.

A 6.9 is a V8 not an I6. Also, there is no comparison between a 444 and a 466. They are in a different class from each other.

pcdreams · 03-09-2016, 03:29 PM

ok sorry about that. I was going by VIN decoder

and apparently not a very good one.

crazycal · 03-09-2016, 04:25 PM

You have a number of options if it is an International. Listed in the order of my preference.

DT466
DT408
444E
DT360
7.3IDI not sure if called 444 also.
6.9 IDI

EastCoastCB · 03-09-2016, 05:52 PM

My order is close to yours Cal.

DT466
DT408
DT360
444/7.3
6.9

pcdreams · 03-09-2016, 06:18 PM

I'm guessing it has to be the 6.9 IDI then.

opus · 03-09-2016, 06:19 PM

Could be a 9.0L

cowlitzcoach · 03-09-2016, 09:08 PM

My order for IHC engines is a little different as well:

DT530 (as any hot rodder will tell you, you can't beat cubic inches)
DT466 (any variation but would prefer the 250 HP version)
DT408
DT360
T444 (sold in Ford products as the 6.9/7.3L/Powerstroke)

EastCoastCB · 03-09-2016, 09:29 PM

Ah, sneaky... the 530!
You're correct, I hereby amend my list to the same as Cowlitz.

crazycal · 03-10-2016, 12:53 AM

I have never seen a DT530 in a bus.

EastCoastCB · 03-10-2016, 05:58 AM

Nor have I.

Booyah45828 · 03-10-2016, 10:40 AM

The old idi's aren't all bad. Yeah they are gutless by todays standards but I've never seen one blown up. They are stupidly simple and seem to always outlast the vehicle they've been put in. They never came with turbos, but they're have been kits over the years to put a turbo on them. Banks still has their offering available. I'd probably choose an IDI over the powerstrokes, especially the 6.0 and 6.4.

It's definitely not a buying point by any means but I wouldn't shy away from it like other engines. Then again, maybe I'm just biased because I own one

. At 1200 bucks, I'd say it's worth a look. Just depends on what your time is worth.

cowlitzcoach · 03-10-2016, 05:23 PM

CrazyCal the DT530 was not available for very many years and it was a costly option so very few buses were built with that engine.

But for the schools that wanted a premium highway cruising school bus the DT530 was a go to option. I have seen more than a dozen over the years and every one of them was a trip bus optioned with all of the bells and whistles.

Skoolydoo · 03-10-2016, 05:30 PM

So I see the DT 408 in all the lists, the one I just got has the 190hp 408 my question is will it hold up maybe another 100,000 if taken care of? It has around 180 now.

Booyah45828 · 03-11-2016, 09:02 AM

They can last upwards of a million if taken care of. All the ones I've seen were extremely durable engines with the proper maintenance. When they went to electric controls the durability suffered somewhat but the core engine is still reliable.

cowlitzcoach · 03-11-2016, 09:54 AM

I would not bet on a million miles but you should have at least 150K trouble free miles ahead of you.

There are a few things that will help you achieve longevity in that engine.

First and foremost, you need to use the proper oil in your engine. DO NOT use the LE formula oil that is out there for sale at places like Costco and Wal-Mart. The LE formula is NOT reverse compatible and does not have the ZDDP additives that the older engines need to go long distances. Whether the oil is Delo, Rotella, Ursa, Delvac, TRC Pro-Spec, etc. you want to get 15W-40 unless you are in a really cold climate where you would want to use 15W-30 in the winter.

Next you need to monitor the pH levels in the coolant. You want the pH to be as close to neutral as you can get. As you go away from neutral in either direction you will start to have issues with scale and electrolysis. It can even contribute to the corrosive action of cavitation when the engine is running. If you don't have a coolant filter you need to put a coolant additive like NAPA's Nacool on a regular basis. Do NOT let the engine get hot. If you are climbing a long steep grade in the summer, if the engine temperature starts to climb to 200* you need to either drop a gear or pull to the side of the road to give the engine a rest. Getting there is more important that getting there fast.

Next you need to make sure the air filter(s) are clean and free flowing. It will slow you down and make you use more fuel if the air flow is restricted.

Lastly, purchase fuel from stations that pump a lot of fuel so that you know that the fuel you are getting is fresh. You can't avoid purchasing bio-blended fuels. Just be aware that the bio-blended fuels do not have the shelf life old fuel had. It will start to lose some of the fire after about 90-days. In addition, the chemicals that keep the bio parts blended are hydroscopic. The chemicals that keep the bio blended also keep the water suspended instead of precipitating to the bottom of the tank. Using a good quality fuel conditioner like TRC's DZL-PEP with AAT will reduce the problems of stale fuel and it will get the water out of the fuel. It will also add lubricity back into the fuel that was taken out when the requirement of low sulphur fuel was mandated.

Good luck and I hope you have a lot of trouble free miles ahead of you.

Skoolydoo · 03-11-2016, 10:49 AM

Thanks a lot, the info will help me keep the beast going a few more miles. We are planing to full time, and being OTR drivers for almost 40 years, we don't plan to run like crazy any more been there and done that..time to stop and see all those things that we had to drive by at a high rate of speed.
I had not heard of this engine before so just wanted to ask.

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