when is a rebuild normally due?

In june of 93 i bought a brand new pete with 6 miles on it, by august of 97 i was rebuilding the motor with 629,000 miles on it.... and it is still running now with over 1,700,000 mile on it. Why it lasted longer the second time i have no idea. In my opinion if you buy anything with over 400,000 on it you should be prepared to rebuild at any time. Had a friend with a fleet of trucks had 2 cummins that didnt last 300,000 but he had a detroit last almost 2 million before he traded it in. If i could pedict when my truck was gonna break down i would fix it before i left home and save my self a lot of misery and money.

 

There's no specific number when a rebuild is going to be called for. Best things to do is make sure that the engine gets a good dyno run before you buy it and make sure that you are happy with what it shows. Then, as soon as possible, get the engine on a good oil analysis program so you can monitor the metals inside the engine. That will tell you what's happening inside your engine in a way that nothing else can.

As for finances, if i bought a truck with anything over 600k of mileage, then I would have plans, or at least resources to rebuild the engine as soon as possible. You mkight not have to touch it until a million miles, but have the money available in case it does decide to go. Monitor the engine closely, since it is much cheaper to rebuild an engine before it breaks than it is to repair it.

Another strategy to consider is plan on and budget for a rebuild as part of buying the truck. Instead of a 30k truck, look for a 20k truck and have the engine rebuilt or replaced before you start running it. Then you start your business career with a new engine.

A good engine should be a million mile component, but when you buy used you have to take some risk in the process. You can minimize that risk, but it takes some real smarts on your part to make it work for you.

 

What is done when a truck is run on a dyno is the hp to the rear wheels is measured on rollers. Then, based on that info, they can reference back to what hp is being put out by the engine, based on the info received from the dyno run. But hp output is only a small fraction of the results. It also measures torque levels and torque rise, smoke levels, there is a sensor that goes on the radiator cap and a device that can detect blowby gases and bubbling from cylinder leakage, and a bunch of other factors that tell how the engine is performing. And you usually have the ECM downloaded at the same time, which tells you what the engine is set at. Just because the dealer claims it is a 470 hp, doesn't make it so. It depends on the settings in the control box, and at what rpm and how it makes that power.

And given a choice between a bunch of hp, getting big numbers, and having torque, I will always vote in favor of torque. That's what pulls you out of the corner when you are lugging a little bit. It's what helps you top the hill without rowing the gearbox.

 

Contrary to popular opinion, HP really dosen't drop off with mileage. I have seen engines with lots of mileage, and tons of blow-by making rated horsepower untill the day they drop.

 

When is a rebuild normally due?


In Joe's case, roughly 4 weeks after buying the truck and putting it into service.....



Sorry, the devil made me do it!

 

Yeah go figure. A 325,000 Cat 3406E that lived it's whole life at a low HP rating. Ran beautiful, no leaks, no blow-by, no smoke, started as fast as you could hit the button, good oil pressure, and it dies just when I get the bugs worked out of the rest of the truck. Never another Cat. Parts are way way too expensive.

 

Maybe I'm gifted or something.

I ran two trucks that I owned long term, and one of them was a 1989 International 9700, bought with 400,000 on it. When I sold it in 1995, it had almost a million miles on the truck. Now, I did replace all the lower bearings in the truck at 700,000 miles, and they were due...no question, but when I sold it, I had no reservation whatsoever in driving it anywhere. It used only about a gallon of oil between changes.

The other truck was a 1995 Mack CH600. I bought it new in 1995, and traded it three years ago. I put a total of 595,000 miles on that truck, and it was like new inside and out, under the hood, and behind the cab. If it had been a comfortable road truck, I would have kept it, but it just wasn't a good long distance truck. Not one wrench was turned on that engine the entire time I owned the truck.

The trucks being built today (post 2000), are much like the newer cars. With proper maintenance and leaving the engine settings set within specs, there is no reason whatsoever that engine life can go well over a million miles without an overhaul.

The one truck I owned that did have a Caterpillar engine was traded in while under warranty, and I will not buy another one, and I'm not impressed with the newer Cummins engines either, due to their lousy fuel mileages.

I am VERY much a Maxidyne and Detroit Diesel man. Both of my experiences with these engines has been positive in terms of maintenance costs, and they were both very fuel efficient. 7.0 out of both, when I wanted to achieve it.

 

I never ever had one of my Maxidynes let me down. Even the old tired ones ran and ran and ran. I have had lots of luck with 855 Cummins powered stuff too. And some of those Mack's and Cummins were turned way up. Back in the day I has a 237 that would out pull a 425 Cat. I ran it for years like that and all I ever did was roll bearings in and do an oil pump when I first bought it. It did drop a valve seat towards the end, but I had a good head lying around and so it only cost me gaskets and about a day's work.

The only truck I ever had that blew a motor was a 1972 Diamond Reo 10 wheel dump that had a 537 IHC gas job in it. And that was because the drain plug got hit and it ran out of oil and spun a main bearing. That cost me all of about $700 and a couple days work to fix.