I need some advice. I was pulling my trailer on the highway and lost oil pressure. 0 pressure. Before I could get off the road she made the dreaded squeeling and shut down. It will start but knocks...rod bearings?
it's a 98 4.6L 135,000 miles. rebuild or replace?

 

i would replace with a used one with low miles, with the parts cost and labor cost to rebuild your motor you willl be spending a ton more that a good used one.

 

To me it would depend on a few factors:

How quickly you need it back on the road?
How much you want to spend?
What do you want to get back out of it? just back on the road? more power?

Replacement would probably be the quickest and least expensive route. However you still get a used engine. I've seen a few complete 4.6s on CL between $400-800. Could be a low-mileage engine that has been well taken care of, or a ticking time bomb. Check it out before you buy, if you're lucky it'll still be in the truck and you can hear it run. On the plus side, this would give you the opportunity to get a PI engine and pick up some power for your '98. If you aren't planning to keep the Truck forever this might be the best route.

To rebuild would take longer, and naturally be more expensive, But you get a "new" engine in return. If you have the tools and knowledge you can save alot of $$$ by doing most of the work yourself. You'll still need to visit the machine shop for specialized work (crank grinding, valve job, etc). Rebuild gives you the option to do internal mods: cams, ported heads, etc. (you're in there might as well). If you plan to keep the Truck for a long time a rebuild will be worthwhile.

 

you can get a 5.4 complete used localy here for 750-1250 at the dismantlers....thats what I'd do.

 

The body and interior are in great shape, and was plannig to do most of the work myself.
All the used engines I have found have over 100,000 miles and dont see the sense in just dropping that in. What about a long block remanufactored engine? I have looked into that and know the price range. but really unsure about rebuild cost and really wont know till I get into it I guess. I have started removal. Would like to have it on the road by spring. and of course a few mods never hurt!!

 

I would go with a remaned for cost reasons and relabilty. The only reason I would do a Rebuild is so that I have a # matching car but at this point that isn't a big deal only when you get into collector status.