Notes from the Engineering Roundtable

I managed to sneak into an engineering roundtable that opened up at the last minute, just before the concerts started. It was mainly a question and answer session between us and the engineers. We introduced ourselves (I mentioned that I'm the keeper of the TJ FAQ), and then we started asking questions. The questions and answers are slapped together in the table below. (If it wasn't so late at night, I'd format it better.)



Gas gauge in the TJ doesn't read full when filled, and reads empty before the tank is truly empty. Told me to ask the folks in the engineering tent next door (which I did later).
Piston slap problems in a '94 Wrangler The problem is annoying, but it isn't detrimental to the engine.
It's hard to shift from first to second gear in a TJ. They made a note of it, but didn't have a solution.
Squeaky noises after heavy off-roading Stuff gets loose; you need to inspect things more often and get maintenance done regularly.
Any chance the A/C switch can be made separate from the vent/defroster positions, so you can defrost without running the compressor? This will be available starting with the '99 TJ.
Engine buzzes around 75 or 80 MPH. Don't drive so fast; how many states let you drive that fast?
Is synthetic motor oil any good? It's better than regular oil, but you still have to change it every 3000 miles to maintain the warranty.
After towing a Jeep to higher altitudes, it still behaves like it's at a lower altitude. As you're driving it, the computer adjusts to higher altitudes. Towing it prevents that from happening, but the computer will reset if you drive it with a wide-open throttle.
Anything special with the dual top option? No, they're the same hard and soft tops currently available from the factory. It's just a convenience for ordering. They come with full hard doors.
Why aren't the drain holes in the lowest part of the vehicle? Good question.
Tall people can't fit into TJ's. The dash is too low, and the shifter isn't big enough. Can you move the seat back? I don't remember the answer for this, but it wasn't a real fix.
Lots of gear noise
Is the 4.0L axle ratio option changing? Yes; it's currently 3.55 to 1 in the '97, but will be 3.73 to 1 in the '98.
I said the cargo net is too small to hold a lot of stuff. This was after the engineers asked the question
What's the biggest tire you can put on a TJ? Official answer: 30x9.5R15. (Despite the fact many people have put on 31's.)
Best procedure for shifting from 4H into 4L Make sure the transmission is in neutral -- it isn't enough to have the clutch pushed in.
When can you shift from 2H to 4H? At any speed under 55 mph.
Water leaks See the technical service bulletins.
Engine makes rattling noises after shifting. You're shifting too early and it's lugging the engine.

I later asked an engineer about the TJ's infamous gas tank sending unit problem. There's a technical service bulletin on the fact that it doesn't read full after the tank has been filled up, but that the TSB doesn't cover the condition where it says it's empty before it really has only 3 gallons left. He said that it wouldn't hurt to have the change made, and that my tank should read full when it's full, but it might not fix the "empty" problem. The gas tank is fine; it's just that the fuel sensor is kind of screwy. I also asked if bashing the skid plate in would cause an inaccurate reading. He said it's possible, and that it would read "empty" too soon if the sensor was knocked way out of line, but that you'd really have to move it a lot for that to happen. Basically, the inaccurate fuel gauge is caused by the fact that several different groups of engineers worked on this system. I'd like to think that if enough people complained about it, they'd realize what kind of a problem it was, so maybe they'll figure out how to fix it later.

The obligatory links back to:

My Camp Jeep '97 page

Todd's Jeep Page

1997 Wrangler FAQ

The Information Singletrack (my glorious home page)