Welcome!
Safety precedence is Steering, then Brakes
Reliability is Electrical, then Cooling, then Fuel.
Research is a folder full of notes.
Each topic has aspects to cover.
Attention to details is the separation of men from boys.
Download a copy of FSM (field service manual).
“Best Parts”, for example, isn’t press BUY NOW on eBay.
Counterfeit or inferior = genuine problem. This isn’t a forum with a huge following.
But it features long-term, knowledgeable owners. Someone already blazed a path if you’ll find & follow, in main.
Verify book maintenance to TIME and Miles is to date.
1). Fluids & Filters. Belt & Hoses. Xtra fuel filtration.
2). All Sensors
3). Align & Steer slop (tires, shocks)
4). No drag w/brakes (temp test)
5). Shocks & Cab Cushions plus suspension bushings.
6). Motor/Trans Mounts. U-joints.
7). New battery cable system.
8). Starter contacts
9). Alternator spec
10). HVAC evacuate & pressure test
11). Fan clutch plus hub bearing plus tensioner
12). Cummins thermostat.
13). Pull Rad & CAC and clean/test.
Do a survey. An appraisal. Expect to treat whole system, not component-by-component.
Below is big truck daily. It’s important (IMO) to have something very close for a vehicle new to one that’s got some miles on it. Keep on executing as new wear pattern emerges (new owner).
IMO, all that “little stuff” is what gets a vehicle sold. Becomes overwhelming to many. Big stuff is easy, conceptually.
There are tests for big stuff (trans or injectors; find & execute tests). But getting stranded by an old pickup is usually the little stuff. (Not sexy. Not exciting).
And it’s minor electrical degradation, often (hard to diagnose).
IMO, no codes, and if steering & brakes don’t need work, then it’s electrical system make/over (cables & sensors & grounds) that come right after fluids/filters/belt being “okay”.
Voltage/Amp problems cleared up are No. 1 (age) in that sense. New BATT pair after:
https://ceautoelectricsupply.com/product/gen-3-dodge-diesel-truck-battery-cable-kits/
would be ideal start in my mind. IOW, my first subject to cover. If “electrical” (including R&R of worn-down, but still operating sensors) is up-to-date, all else is easier to deal with.
Don’t forget brake controller and trailer harness wiring.
For good or for bad, that $5k can get chewed up fairly fast by
high potential reliability issues.
Service needs: Best code reader, some specialty tools, workplace safety (XHD Jack stands and wheel chocks kinda stuff), etc. A 4,800-lb front end needs respect.
If I need a tow, I prefer a rollback. But I have to emphasize that the pickup weighs 9,000-lbs. Same with some shops (vehicle lift capacity).
So it’s also a breakdown kit (flares, triangles, rain suit, coveralls, work light). All new external lamps. New, clear headlight assemblies. Etc.
Back into the operational needs prior to sweating major line item expenses.
I could see $3k for (5) tires, shocks, specialty & workplace safety tools plus Class A breakdown kit, maybe a couple of sensors,
alone.
These trucks aren’t cheap to own/operate.
Need a numerical baseline. Get a CAT Scale reading (max fuel, driver-only plus gear that never leaves truck ONLY.) Adjust cold tire pressure to that spec (probably 50 FF and 50 RR). Use FUELLY or similar to track MPG.
RECORD Odo Miles and Engine Hours now.
The relation of:
— Average MPG
— Average MPH
are keys to understanding how it’s responding to use conditions, and changes may mandate investigation prior to warning lamps or codes.
Cummins & Dodge make prediction on how long that engine will go prior to $$$$ repair or replacement (350k, for half of all examples). I’d want electrical, “like new”, first, and would be looking at new injectors
plus associated parts (past upgrading fuel filtration) as the
major expense to be tackled past any safety-related.
$5k is a good start. $10k is likelier over the near term (first few years).
How long will you keep it, and how many miles will it accumulate? This is the beginning question set. “The Big Picture”. Make a good approximation and start the numerical baseline with true data (no guessing).
Good luck.
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