Rusty 720 diesel

[CRD]

I'm wondering if the cab from that 84 would work on my 81? It's a different dash setup and the dash in the wrecking yard truck is trashed. My cab has rust issues ad the right inner fender needs to be cut out and swapped. Maybe a cab swap would be easier. It would give me a chance to strip and paint the spare cab ahead of time so the truck is down for less time. What do you guys think?

[wayno]

Is the 84 a kingcab?

If it is, it will bolt right on, as all kingcab cabs are the same, but the wiring is not the same, you will have to use which ever diesel harness fits the instrument cluster you use, round gauges need the 84 diesel wiring harness, square gauges need the 81 diesel wiring harness.

You can put your 81 wiring harness in the 84 cab, I have done this before without issues, but you have to pull dash and everything else on the firewall to do it, well you don't have to pull the steering column, but you do have to pull the e-brake lever assembly.

You might be able to use the 84 diesel cab complete(wiring harness/gauges/column/ect.), buy you need to check which type of glow plugs the 84 uses, as there are two types, fast and slow, and it messes them up if you have the wrong type for your glow plug timer, meaning if you use your slow to warm up glow plugs on a fast glow plug timer, it likely will be hard to start, if it will start at all, and if you use a fast glow plugs on a slow glow plug timer, it will start great the first time, because they will get hot as the sun, and the end of them will blow up like a balloon, but they will never work again, so the next day it will not start, and it is very hard to remove them after the end blows up like a balloon, I had to use vise grips and pull and twist very hard to get them out, I am lucky it did not mess up the threads in the hole.

You can also use your 81 dash in the 84 cab, but I am not sure of the legalities of doing this, as the VIN number is on the dash, and there is also the vin tags on the door jam pillar, and in the engine compartment to think about.

[CRD]

I'm going to work on it tomorrow, new breaks and front wheel bearings. I need to size up the cab I have and decide if it worth fixing. Both trucks are king cabs. Thank you for the info Wayno, I appreciate it.

[CRD]

Changed the front bearings and rear breaks. While investigating a leaky rear wheel seal I found the bearing welded to the axle. I found an axle shaft at another yard and installed it. I'll take it out for a good drive in the next few days and see how the repair holds.

[wayno]

You sure it was welded, they normally are pressed on, and they don't come off easy.

[CRD]

I tried every means of persuasion available to me with no luck. There were also some dings in the shaft right where the inner seal rides. I cut the old bearing with a cold chisel and it still didn't budge. It was bad enough to make me not trust the axle to hold a bearing or a seal again.

[CRD]

This weekends project is to find some tires and wheels for the 720 without breaking the bank.

[Nissan_Boy85]

As long as you put the correct VIN tag on whatever dash is in the vehicle, there's no problems. I replaced the complete dash in my 85. Removed the tag of the "new" dash that wasn't for my chassis, put the correct tag on after pulling it from the old dash. Just a FYI.