Potential new ford diesel owner - need advice please!

[Pruitte27]

Hey guys,

I'm new to the the ford diesel world and need some questions answered and advice about a truck I'm looking at. I found a 91 f350 for sale for about 5 grand. Right around 208,000 miles. New water pump, throttle cable, radiator hoses. No turbo (I don't think any 91's had turbos but I could be wrong.) Questions Below

1) is 5 grand a decent deal? Body looks great for a truck this old

2) I will be hauling a small two horse trailer once or twice a month on short road trips (2 hours or less). Will this truck fare okay with that workload? Will not having a turbo affect that?

3)I've read about the "death wobble", but other than that are there any major issues that occur frequently with this truck?

 

[SuperCab]

5k seems a little high for that but it depends what part of the country you're in. If you've been shopping around you should have a feel for what's reasonable near you.

It was a good engine for its time. Pretty lackluster by today's standards but reliable and fairly efficient under the right conditions. It would certainly pull your horse trailer.

Runs in my mind those had a lot of issues with glow plugs when they got older. I'd want to see it cold start if possible just to make sure everything is good.

Death wobble is common on lifted trucks with oversized tires. If you're running stock suspension and stock sized tires your chances of having that issue are exponentially less.

There's a few guys on here that have trucks with the idi 7.3. Hopefully they'll chime in

Oh, and welcome to the site!

 

[Pruitte27]

Thanks! 5k is a little high, but here in tennessee diesels are always high.. I've seen trucks with awful bodies and torn up interiors for the same price.. he said sometimes it takes ether to get it started if it's extremely cold.. are glow plugs a hard/expensive fix?

 

[Fellro]

Factory issue, no turbos. You can definitely add one though. They won't get you there fast, but they will get you there with the house or two behind you... Stick or auto? Overdrive is something that is a major help with these motors. They don't like being spun too fast, or they get quite thirsty. I used my 86 towing a 5 horse slant through the mountains of Virginia... I was slightly faster than the semis, but certainly no speed demon. Nice thing is, as diesels go, they are relatively inexpensive to keep moving. The whole set of injectors can be had for the same or less than just one on a newer electronic engine. Injection pumps are about $3-600 depending on source and power setting.

 

[Pruitte27]

Great info, thanks! It's an automatic.

Had a friend tell me these tricks had a lot of suspension issues (gearbox, ball joints, tie rods, etc.) what do you think about that? He's always been a molar/dodge guy so I'd rather hear it from ford guys

 

[Fellro]

Automatics of that age had issues, but if it has been rebuilt many times they get the issues resolved. Typically, a good aftermarket rebuild can take care of what the factory lacked.

It is unfortunately pretty common for the steering box to be loose, but if you drop the cash on a Red Head (a company that does rebuilds) steering box, you generally won't have an issue from there on.

The glow plugs are already the updated set up that many upgrade to. The early controllers like on my 6.9 had a history of failure, and it was fairly common to upgrade to the newer style like that truck would have.

As to the tie rods and ball joints, I have had my 86 6.9 IDI for 14 years, and the tie rods went bad once, glow plugs twice, ball joints are the same as when I got it, clutch once, same steering box, and it has been rode hard and put away wet quite a lot. I bought it to pull trailers and haul loads, and that is what it has done most of the time. I was hauling a 40 foot trailer loaded with scrap regularly for a few years. I scaled in total actual weight of 24,500 pounds on one run... I knew I was heavy, as it did pull down on some hills (not mountains... ) but kept plugging right along.

 

[Pruitte27]

Thanks for the help fellro. 8' going to check it out this afternoon.. other than checking leaks, rust, etc is there anything I should specifically check for to make sure it's in good shape?

 

[Sparky83]

pull the dipsticks to check the fluid conditions. dark or burnt smelling fluids can be an indicator of lack in maintenance.. unlike gassers, diesels are very sensitive to maintenance when its neglected because they work with tighter tolerances. if the oil smells burnt it can be an indicator of pumps failing, insufficient oil coverage in tight places, or being left for to long making it acidic.

down side with the oils not being changed means that deposits have had a chance to build up in areas they normally wouldnt have. and then when you go to do services in these areas it can open new problems you didnt know existed when the cleaner fluid and filters clean it out..

 

[Pruitte27]

Just got done checking it out.. only a little bit of surface rust in the driver door jam. Some trim pieces broken and minor stuff, needs tires. 4x4 works perfect. Test drive went well, only two things I noticed were a little play in the steering wheel and it shifts from first to second a little hard.. the owner said it was because it has a shift kit on it, but I'm not sure what exactly that means

 

[Fellro]

The valve body in the transmission was modified slightly to allow for faster, firmer shifts. The idea behind that is to get the clutches engaged faster so as to reduce wear and slippage. As long as the timing of the shifts seemed right, then it likely is truth. Diesels have no vacuum, so the early automatics had to use a valve that was put on the side of the injection pump and had a vacuum from the vacuum pump to operate the modulator on the transmission. They can be a bit off and cause harder shifting. It isn't quite like a gas that has variable vacuum, the pump only generates a vacuum to a certain level that is constant rather than variable.

 

[Pruitte27]

Okay, so the hard shift is likely nothing major then it sounds like. Thanks for all the info.. I'm going to check it out one more time and likely buy it this week.

For future reference, I fully expect to have to rebuild the engine and or tranny one day. I'd like this truck to last another 2-3 hundred thousand. How expensive of a process is it to rebuild?

 

[Fellro]

One key thing on the 7.3 is be sure to use the higher grade antifreeze. The vibrational nature of the diesel tends to make for a hard time on cylinder walls that erodes them away by a process known as cavitation. The higher grade fleet coolants have anti-cavitation agents in them. It is possible to buy an additive as well for that.

Typically, if maintained properly, these motors outlast the trucks they are in. It isn't impossible to have them rebuilt, but that can come from plenty of reasons. Some motors go easily 500,000 on original build, others don't. But they are also more expensive to do, and the 7.3 is already bored out quite a bit so it isn't a good thing to do. You can sleeve the block, but there again, it is a trick to find a shop that can do it right and keep them from moving around. They are not a sleeved motor from the factory. Rebuild kits range from $800 and up. As with anything, it depends what all you want to do at that point.