TJ oil pressure gauge showing unfamiliar unit of measurement

Shandara

TJ Enthusiast
Joined
Jan 5, 2019
Messages
111
Location
Okanagan
Hi new member,

Long time Jeep owner. I have had at different times a CJ6A, CJ5, CJ7, grand Cherokee, YJ and a couple of TJ's. Just bought another TJ for camping and fishing. It wasn't really the plan but it was in really good condition rust wise and the price was one I couldn't pass up. It runs reasonably well, I will need to do the exhaust manifold and possibly the down stream O2 sensor but everything else seems to be in good shape. Yes I know about the manifolds cracking and to avoid the bosche sensors. I actually worked for a Chrysler dealer for a while and have not seen this before nor can the local dealer service department tell me what I have. The oil pressure gauge is using a unit of measurement that I am not familiar with. I have found occasionally a similar gauge in online photos and one you tube video where the guy is showing his oil pressure issue that has the same gauge. Markings are 0,3 and 5.4. I do not have any reason to believe I have any oil pressure issues but would like to know what measurement it is so I can do the math. If someone is familiar with this gauge I would appreciate knowing what it is. And yes I searched all 10 pages that came up in relation to oil pressure gauge on the site with no joy. Thanks in advance.

Kevin.

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Doing some quick math, it looks to be approximately 100's of KiloPascels. Convert from psi to kPa and divide by 100.

40 psi = about 278 kPa and 80 psi = about 552 kPa. Close enough for TJ oil pressure gauge accuracy.
 
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This is weird. Did some TJs come stock with this sort of unit measurement?

Regardless, the factory oil pressure gauge on TJs is notoriously accurate. I wouldn't even pay attention to it at all.
 
It's a Canadian TJ (not Wrangler) with the metric cluster.

Oh... that explains it. First time I've seen it I guess.

I didn't see any mention of Canada in the original post, hence my confusion. Not if I was looking for an "accurate" reading of course.
 
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Oh... that explains it. First time I've seen it I guess.

I didn't see any mention of Canada in the original post, hence my confusion. Not if I was looking for an "accurate" reading of course.

Easy to tell it's Canadian by the TJ instead of the Wrangler emblem
 
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Easy to tell it's Canadian by the TJ instead of the Wrangler emblem

Somehow I missed the second photo. That's what I get for using my phone. I tend to just scroll more on the phone than I do on my desktop.
 
I can see where that would seem to make sense for the most part however my 99 TJ had an oil gauge showing PSI, several other TJ's I know of and have been in are in PSI and the local dealer here in Penticton, Canada has no clue about that particular unit of measurement. Not that I would go out of my way to deal with it but if I happen across a TJ being parted out I am wondering if I replaced the cluster with one including the PSI measurement if it would be plug and play to get me back on familiar ground?

Kevin
 
if I replaced the cluster with one including the PSI measurement if it would be plug and play to get me back on familiar ground?

Maybe, but maybe not.

This would depend on whether or not that measurement is a variable stored in the PCM or not.

You could certainly try it and you may get lucky. However, there's also a good chance that the PCM itself is telling the gauge cluster that it wants the output to be in a different form of measurement.

I know when I access my PCM via the HPTuner software, there's a setting to change from KPH to MPH. That seems to suggest that measurement units are stored in the PCM, not the gauge cluster... which actually would make a lot of sense.
 
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I can see where that would seem to make sense for the most part however my 99 TJ had an oil gauge showing PSI, several other TJ's I know of and have been in are in PSI and the local dealer here in Penticton, Canada has no clue about that particular unit of measurement. Not that I would go out of my way to deal with it but if I happen across a TJ being parted out I am wondering if I replaced the cluster with one including the PSI measurement if it would be plug and play to get me back on familiar ground?

Kevin
Yup, should be PNP, I would think.

Maybe it came from Quebec. Those French can be quite stubborn about their units of measurement.
 
I can see where that would seem to make sense for the most part however my 99 TJ had an oil gauge showing PSI, several other TJ's I know of and have been in are in PSI and the local dealer here in Penticton, Canada has no clue about that particular unit of measurement. Not that I would go out of my way to deal with it but if I happen across a TJ being parted out I am wondering if I replaced the cluster with one including the PSI measurement if it would be plug and play to get me back on familiar ground?

Kevin

You can just get a Gauge Face Overlay that reads US from Ebay or similar places.
 
I have seen those when I was trying to figure out what mine is reading in and it crossed my mind and then it dawned on me that It would mess with the Speedo and water temps. It seems to me I have seen a TJ with just a low and high on either end of the scale which would work if I ran across one cheap enough. More likely though is once I'm use to it, it really won't matter in the long run as long as I personally have a good idea of what it is actually representing.

I appreciate the info. Thanks

Kevin.
 
I have seen those when I was trying to figure out what mine is reading in and it crossed my mind and then it dawned on me that It would mess with the Speedo and water temps. It seems to me I have seen a TJ with just a low and high on either end of the scale which would work if I ran across one cheap enough. More likely though is once I'm use to it, it really won't matter in the long run as long as I personally have a good idea of what it is actually representing.

I appreciate the info. Thanks

Kevin.

I cannot imagine that Jeep would produce different computers/sensors for metric and US production, very simple to just print different gauge faces for each market. Replacement gauge faces should read correctly either way. It would be simple to compare lets say your coolant temp needle position (at normal temp) to a US market gauge and it's position at normal operating temps.
 
It's all good. I thought someone may have run across it before and could tell me what it was so I could do the math in my head when I read it. I'm not particularly worried about the pressure assuming the 3 is equivalent to 40PSI give or take a bit, it has good oil pressure. It does move in relation to RPM changes which I expect. Nothing like my old CJ that once warm would drop to about 15PSI at idle. I have fairly long laundry list of things I plan to do to it to get set up for fishing, camping and off roading. Very little will get done between now and mid April when I get pocession of my new house. Most likely very little other than a small list of things for safety and proper maintenance will get done after I get pocession until fall and I expect I will probably be fully comfortable with that gauge by then.
 
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