How to Buy a Used Budget Jeep – Engine & Drivetrain Choices


First thing you need to decide is the intended use of your Jeep. With today’s gas prices every bit counts. If you’re looking for a little freedom drive and small commutes in town, the 4cyl engine will do you fine. If you travel frequently on the highway or interstate definitely need the 6cyl. Either engine will do fine off-road with the gearing provided by the transfercase. If you are looking for a project budget Jeep for off-roading that will get a new engine then you still have the engine to consider as it will affect your bottom line; 4cyl engine Jeeps are cheaper.

Since this is about Wrangler or YJ Jeeps we won’t touch the others at this time. In 1991 Jeep introduced the fuel injected 4cyl engine. It pushes out 123hp and 139ft/lbs of torque. Transmission and transfercase with this engine is the AX5 and NP231. The AX5 is a lightweight transmission and when you test drive you will want to verify smooth shifting from 2nd the 3rd gear as they are known for bad sychro’s (aka grinding will occur). The NP231 is a chain driven transmission and will stand up to any abuse you will throw at it with the 4cyl and has a respectable 2.71:1 reduction for off-roading. If you’re looking for a town putter, easier on gas, able off-roading and open air driving to the beach this is for you. Best thing about these engines is the price, but if you want an auto they will be gutless and hard to find.

Also in 1991 Jeep had the 6cyl as an option or standard depending on the model. The 6cyl Jeep engine put out 185hp and 220ft/lbs torque. These engines came with the medium duty AX5 transmission and the same NP231 transfercase. A bit harder on gas and pocket book, this engine is what most look for as it has the guts on the highway/interstate. They also come plenty in automatic and standard transmissions. A good catch in the 6cyl model is the heavy duty Dana44 rear axle that you can stumble upon in Jeeps that came with towing package. These rear axles can handle more abuse then the stock Dana35.

Unfortunately Jeep Wranglers did not come from factory with a V8 so if you come across one for sale take a good look at the engine harness and ask lots of questions. Last thing you want to do is inherit someone else’s problems. We will go deeper on this in another article.

So you have a lot of choices. Best to be educated and know what you are looking at so you can make an informed decision. The buying decision will be totally different between someone looking for a cruiser or and offroading project. As they say: “Your mileage may vary”

This part three of a six part series I’ll write.

Stay tuned for:

– How to accessorize your Used Budget Jeep

– How to build a mild off-roading Used Budget Jeep

– How to upkeep your Used Budget Jeep

Hope this was informative and helps you discover the Jeep addiction. Keep it Jeep!