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8 Tips For Buying a Used Diesel Vehicle

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Things To Look For When Buying a Used Diesel Vehicle

Buying a used diesel vehicle can pose some major benefits to those looking for a great ride, at a great price.

When buying new isn’t an option, used diesel vehicles can be reliable alternatives to straight off the lot- as long as you know what you’re looking for.

Unlike new, used vehicles don’t have service or parts warranties, nor do you have the guarantee of vehicle backgrounds and accident history. While there are many great sellers out there, you’re entering a marketplace where anything can go. We’ve seen some nightmare situations here at the shop- unknowing buyers purchasing used vehicles that have ended up being complete duds.

You can avoid this by knowing exactly what to look for before you see the vehicle, and what to look for while taking it for a test drive.

Particularly with used diesel vehicles, there are specific things you should be on the eye out for- to avoid costly repairs and failures down the line.

Check These Eight Things When Buying a Used Diesel Vehicle

The Exhaust

Diesel vehicles burn diesel in quite different way than a gas engine.

Diesel is a lot thicker than gas, so when it burns, there is always a small amount of soot that comes out of the exhaust. When you look at the exhaust, some soot present is fine- and normal. Excessive soot however, indicates a problem with the engine combustion or just in the exhaust itself.

Now, excessive soot could mean that the vehicle just really desperately needs an oil change. Usually though, it signifies more serious underlying problems that are likely going to cost you a penny or two.

The Color of the Oil

Something that we see buyers overlook very often is the color of the oil.

Its probably something you don’t think to check, but a pale or milky oil indicates big problems with the engine and a replacement will likely be needed.

Oil around the gaskets indicates that the gasket has lost it’s integrity and leak. Not only does this cause oil leakage- another red flag- but it can also affect engine performance and drivability.

If this isn’t replaced in time, bad valve cover gaskets can lead to complete engine failure. So check for that oil!

Starting The Car

As much as we love our diesel rides, it’s common knowledge that with a few miles on the clock, diesel vehicles do get harder to start in the cold. Simply because of the thickness of diesel fuel vs. regular gasoline, it’s harder for the fuel to move through the lines in extreme cold.

(Diesel vehicles in Saskatoon winters are no stranger to this problem.)

Start the vehicle from a cold start and see how it cranks over. A long start time likely indicates problems with the glow plugs in the head.

While these are absolutely replaceable, it gets pricey.

Dirty Radiator Fluid

One of the biggest causes of overheating- dirty radiator fluid. Cooling system failures are the biggest causes of roadside breakdown, and unfortunately- there are a few reasons why this may be happening.

Be sure to check out the radiator, and look at the fluid. If the color is off, inconsistent or the liquid is sludgy- keep walking to another vehicle.

Additives, contaminated coolant & corrosion are just a few reasons why your radiator fluid would be less than ideal.

A Smokey Exhaust

Make sure the car is running when you check to the see the condition of the exhaust coming from it. A thick or white color- vs. a healthy light black- indicates a potential problem with the engine.

Usually, this is due to the cylinders needing to be replaced or bored- but it also could mean that the fuel/air ratio is off.

A Funky Stink From the AC Unit

When you turn on the car, a foul smell from the AC unit is actually a good sign that the vehicle experienced some flooding- or that the owner let it sit and rot a bit before selling.

A Noisy Engine

Diesel engines are notoriously louder than gasoline engines; this is a given. So, when starting the engine of a used diesel vehicle, the roar will be louder.

Not too loud, though. An obnoxious roar- especially when going over bumps or up hills- typically indicates that the engine has been overworked and will need a replacement soon.

Tire Inconsistency

The tread on tires can be a huge indicator of how a used vehicle has been handled while driven. Aside from the obvious of staying in alignment and vibrations, you should consider the tread.
Too much wear on the inside or outside of the tires usually means there was handling problems somewhere in the vehicles driving career.
Notice cupping within the tire? That’s likely caused by irregular vibrations, so switching out the tires only fixes half the problem.