fuel gauge

fljeeper

TJ Enthusiast
Original poster
Joined
Feb 7, 2016
Messages
138
Location
Bradenton, Florida
I just added TJ number two to the collection. It is a 97 SE for my 15 year old son since he likes my 98 Sport and off-roading. It needs various odds and ends and he is learning to repair and maintain it along the way. We just finished installing a complete exhaust, Flowmaster headpipe and cat and Dynomax cat back with new o2 sensors. Next on the list is the fuel gauge. The fuel gauge stays at full. When the key is out of the ignition is shows full. When you first turn the key to run/start the gauge drops down to empty and then goes to full. Any recommendations for how to locate the culprit? Also, I nee the cover to the power distribution box (next to the air filter cleaner). Jeep discontinued this part so does anyone have a source? One more question for now, the Haynes shop manual indicates that the ax5 transmission can take GL5 oil. Is this correct? I ask because of my ax15 needing GL3 and we want to change all the fluids soon.

Thanks,

Daniel
 
I just added TJ number two to the collection. It is a 97 SE for my 15 year old son since he likes my 98 Sport and off-roading. It needs various odds and ends and he is learning to repair and maintain it along the way. We just finished installing a complete exhaust, Flowmaster headpipe and cat and Dynomax cat back with new o2 sensors. Next on the list is the fuel gauge. The fuel gauge stays at full. When the key is out of the ignition is shows full. When you first turn the key to run/start the gauge drops down to empty and then goes to full. Any recommendations for how to locate the culprit? Also, I nee the cover to the power distribution box (next to the air filter cleaner). Jeep discontinued this part so does anyone have a source? One more question for now, the Haynes shop manual indicates that the ax5 transmission can take GL5 oil. Is this correct? I ask because of my ax15 needing GL3 and we want to change all the fluids soon.

Thanks,

Daniel
Try to run a diagnostic on the instrument cluster to see what the gauge does. You hold the odometer reset while turning the key to the run position. You could also unplug the connector at the tank harness to see if that has any affect on the gauge. You could probably get a power distribution cover from Daveys Jeeps, he's usually right on with that stuff. For the trans I would use Redline MTL which is a top notch product and my AX5 loves it. It's available at Summit or Amazon.

http://www.daveysjeeps.com/
 
The fuel gauge sender is on the fuel pump assembly Daniel. But first, before replacing it, check its electrical connector located externally up high on the driver's side of the gas tank. That connector includes wiring for the fuel gauge sender and fuel pump.

Most GL5 gear lubes are bad for the synchros inside the transmission. Unless the GL5 container specifically says 'Safe for yellow metals', don't use it. Only old outdated manuals will say GL5 is the right stuff. It's best to use a GL4 75W-90 like Redline MT-90. Redline MTL will work but MT-90 has the exact factory recommended viscosity.

Or, believe it or not any good quality synthetic 10W-30 motor oil was announced by Aisin as suitable. No worries, 10W-30 motor oil and 75W-90 gear lube have essentially the same viscosities since they are measured on two different viscosity scales.

I hope that was of some help.
 
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I just added TJ number two to the collection. It is a 97 SE for my 15 year old son since he likes my 98 Sport and off-roading. It needs various odds and ends and he is learning to repair and maintain it along the way. We just finished installing a complete exhaust, Flowmaster headpipe and cat and Dynomax cat back with new o2 sensors. Next on the list is the fuel gauge. The fuel gauge stays at full. When the key is out of the ignition is shows full. When you first turn the key to run/start the gauge drops down to empty and then goes to full. Any recommendations for how to locate the culprit? Also, I nee the cover to the power distribution box (next to the air filter cleaner). Jeep discontinued this part so does anyone have a source? One more question for now, the Haynes shop manual indicates that the ax5 transmission can take GL5 oil. Is this correct? I ask because of my ax15 needing GL3 and we want to change all the fluids soon.

Thanks,

Daniel
Although it's better than nothing, try to find a factory service manual: Amazon, eBay, Craig's list,etc. Than get rid of that Haynes. They try to cover too much. I have had several for several different vehicles. All of them went into the garbage.
 
Not only do the Haynes and Chilton's manuals try to cover too many model years in one small paperback book, much of the information in them is flat out wrong for some model years. They''re only useful for minor stuff that doesn't really change like changing the oil or brakes.
 
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I did the hold the odometer reset while turning the key to run and the odometer went from 111111 to 222222 to 333333 all the way to 999999 while all the gauges swept from their low range to their high range including the fuel gauge. What am I looking for here?

Thanks,

Daniel
 
I did the hold the odometer reset while turning the key to run and the odometer went from 111111 to 222222 to 333333 all the way to 999999 while all the gauges swept from their low range to their high range including the fuel gauge. What am I looking for here?

Thanks,

Daniel
You were looking to confirm that the gauge operates thru the range which as you stated it does, that at least confirms the instrument cluster side is good to go. Next step is to check the harness connection which is located on the drivers side just forward of the tank. I would separate the plug and inspect the contacts and condition of the wiring on each side of the plug. Some contact cleaner would not hurt also. Beyond that if necessary the tank may have to be dropped for inspection of the sending unit.