1999 Jeep Wrangler TJ 4.0 I-6 from North America


Piece of crap


From 114K to 140K miles the following happened -

Manual transmission shift fork wore out and the transmission would slip out of 1st gear. The transmission was rebuilt.

Radiator leaked and was replaced.

Engine misfired erratically, so the ignition spark coil replaced.

Fuel sending unit check valve went bad and the sending unit was replaced (had to crank the engine for 10 seconds while the fuel pump filled the line to the engine).

Blower motor resistor replaced.

Exhaust system rusted out and was replaced.

Brake drums replaced.

General Comments:

This is supposedly an "off road" vehicle, but it does not even have a limited slip rear differential. In 2WD you can get stuck in the winter, with one wheel on dry pavement and one wheel in the snow.

14 city/18 highway MPG.

Extremely bumpy ride.

With a soft top, there is so much noise that you need to yell to talk to someone sitting right next to you, when going down the expressway at 70mph.

Would you buy another car from this manufacturer? No

Review Date: 25th April, 2014

11th Jun 2014, 14:52

You bought a used Jeep with over 100,000 miles on it. If you wanted a Camry, you should have purchased one. The 4.0 liter engine is absolutely bulletproof. A Wranger is far from being a "piece of crap".

1999 Jeep Wrangler Sport 4.0L from North America


Very reliable and a fun vehicle to own!


Replaced cracked exhaust manifold when I first got the Jeep.

Replaced the front and rear brakes.

Replaced both headlights after one burnt out shortly after buying vehicle.

General Comments:

Not a very fast vehicle.

It has the aerodynamics of a shoebox.

Hardly any trunk space.

Only gets around 15mpg.

Rear bench is not very comfortable.

The Jeep was great power and torque to get through any type of terrain.

Perfect vehicle to drive in the summer with the top off.

Perfect also in winter with 4x4 engaged.

The Jeep Wrangler is a perfect vehicle for someone like myself. I don't really care that it gets low mileage to the gallon, it is a Jeep so that comes with the territory. I do and keep up with all the regular maintenance including oil changes every 5k, with full synthetic, transmission fluid will be changed every 30k, and differential fluid will be changed every 30k as well. So far this Wrangler has never failed me. It will start no matter how hot or cold it is outside.

The abundance of aftermarket parts and accessories is at times overwhelming. With so many options available you can always be assured to find something for your Wrangler when you need it. Whether it is bumpers, lift kits, off road lights to drivetrain components and engine parts and add-ons, there will always be a surplus of options to choose from.

Would you buy another car from this manufacturer? Yes

Review Date: 1st June, 2009

1999 Jeep Wrangler Sport 4.0L V6 from North America


Unreliable - expensive major repairs


1) Coolant leak - internal to engine head - cracks - very expensive repair ($1200 to $2500 +)

2) Overheating

3) Oil pressure low - (gauge) 0 at idle! And lower as engine warms up - check gauges light

4) Coolant contaminates oil

5) Coolant contaminates catalytic convertor

6) Air conditioner system failure ($3,500 repair) - air divertor door also sticks.

Not just a Wrangler problem - these problems are across Jeep product line using common engine (4.0 l V-6) and components!!!

Would you buy another car from this manufacturer? Don't Know

Review Date: 6th November, 2008

8th Nov 2008, 07:33

First of all the 4.0 liter engine is not a V6 - it is an in-line six.

Secondly, this engine is as close to bullet-proof as you can get. They are not a problematic engine at all (as you suggest).

Between myself and my wife, we have owned 4 Jeeps equipped with the 4.0 liter engine and never experienced any problems at all. Ask any Jeep enthusiast about the 4.0 and they will tell you that it is one of the best engines ever built.

8th Nov 2008, 21:44

I agree, having owned 2 jeeps (1991 Comanche, 1990 Cherokee Laredo) with the in-line 4.0 six cylinder, it is a bullet-proof engine, no problems! The Comanche has 186K on it, still going strong, and the 1990 Cherokee has minimal mileage for it's year, 100k, but has not even the first oil leak or any concern at all! If manufacturers made engines and autos like this today, they would not be facing possible bankruptcy.

9th Nov 2008, 14:30

My current Wrangler (a 1995 YJ Sport) equipped with the 4.0 liter six, has approx. 140,000 miles on it, and it still runs like new. It does not burn any oil. It doesn't leak any oil.

I have not had one issue with it. Great engine!

11th Jun 2014, 22:27

I only wish they still manufactured the 4.0 liter inline six. Every vehicle I've ever owned with this engine was a delight. It may not be the greatest in terms of fuel efficiency, but it more than makes up for being a bit thirsty in terms of reliability.

Also you have to keep in mind the vehicles it was installed in were not exactly aerodynamic, nor were they econo-cars. They were rugged, brick shaped Jeeps, some weighing in excess of 4,000lbs.

I once read that the 4.0 liter engine reportedly could trace its roots back to a 1920's Nash design.