I just bought an 01 dakota rt with 106k miles in really good condition. I bought it on the 26th and the oil pressure was over 50% and has been until today. The oil pressure dropped down to the inner left mark of the gauge (second mark to the right next to red). I checked the oil and the level is good. Is the oil pressure good at that level or is something wrong?

I just scheduled an appointment for friday to have it looked at by the dealer I bought it from but would like to hear what you have to say. thanks

 

It kind of depends. On a hot idle if the gauge is right above the left hash mark that is normal. As you drive the truck and the RPM's increase, the gauge should move too. On my own truck the gauge stays just below the right hash mark when cruising on the interstate at 70 mph and about 2000 RPM and just above the left hash mark when idling at 600 RPM at normal operating temperature. Driving around town at varying speeds and RPM's, the gauge moves in proportion to the RPM's. The oil pump is engine driven so that is normal operation. It is not normal for the gauge to be at the lower end or decreasing when you increase the RPM's.

The oil pressure gauge is not all that reliable and it may not always tell you the truth about your real oil pressure. The OEM oil pressure sending units have been known to fail or give bad readings. It is a common problem on Dakota's. The best way to check the oil pressure for sure is to remove the OEM oil pressure sending unit and install a mechanical gauge. You can temporarily duct tape it to the windshield and take a test drive to see what your real oil pressure is. You could also replace the OEM sending unit and/or clean the wire harness connector on top of it and see how the pressure does then.

Personally I would be very cautious about what the dealer tells you. You could probably check, diagnose and fix the the oil pressure yourself for less than what the dealer might charge you. If you need a new sending unit it should cost around $30.00 to $35.00 at most good parts stores. A Dodge dealer will charge you anywhere from $80.00 up to $125.00 just to pull the truck into the shop for a diagnosis.

Jimmy

 

This is good to know. On my dakota it does the exact same thing as yours Silver. At a cold Idle it is just below the right hash mark. At a hot idle it sits just above the left hash mark, and as I accelerate it goes back closer to the right hashmark.

I was unsure of this as well, as Ive always just seen the pressure gauge in previous trucks at one steady position hot or cold, idle or accelerating.

 

Thanks for the help. I`m paying for a 2 year 24000 mile warranty so I may as well see what the dealer has to say. Its an awesome truck though. Interior is showroom clean, body is real good looking, and underside is about rust free.

 

if you go WOT and the oil pressure is pegged on the LOWER mark you got issues. ive been there a few times before my motor blew. as long as fluid level is full you should be fine. the oil warning light wont come on untill there is like 1q of oil left, which is a dumb design, i had it down to like 2-3 quarts and no light.

 

My durango (basically the same design) had an issue when I bought it where randomly when I started coming to a stop my oil pressure gauge would drop. Never figured out what it was, oil levels were fine, did a tune up and went and got an oil change one day and boom, never came on again. Yes I took it somewhere for an oil change. I was feeling lazy that day. Did the tune up myself though.

 

The oil pressure changes some with acceleration but not like I think it should. It was over half way mostly and now its not making it to half way even with the pedal at the floor. I`m going to have the dealer check it out today.

The truck has a slight main seal leak. I dont see why pressure would change so much all the sudden though since its had this leak since I got it.

 

Seal leak could have opened up more, i mean even a little bit can cause pressure to drop I would think. Have you tried getting an aftermarket gauge from like advance or autozone and hooking it up? Might just be your guage is wrong.....

 

I had it looked at and it works as it should. Oil pressure should be about 6lbs at idle and about 30-80lbs at around 3000 rpm

 

The oil pressure itself may very well be OK, but a sudden drop in the gauge reading could indicate a bad sending unit or a wiring/connector problem. Not trying to tell you your business but if this were my truck I would still put a mechanical gauge on it to find out the real oil pressure. Bad oil pressure sending units and erratic gauge readings are a common problem with Dakota's. The slight leak on the rear main seal is even more reason to be sure the gauge is displaying the correct oil pressure.

If the dealer just looked at the truck and did not connect a mechanical gauge to tell for sure that the oil pressure is actually OK, then it sounds to me like that is an incomplete diagnosis. Not trying to throw the dealer under the bus but sometimes dealers will find ways to not do certain jobs when the vehicle is under an extended warranty, because they do not get paid as much as a customer-pay job. Once that extended warranty runs out, the dealer will probably be able to find a whole bunch of problems they want you to pay them to fix.

On this oil pressure problem, I would either check it myself or take it to a trusted shop for a complete diagnosis. if there is a Harbor Freight store near you, you can buy this gauge set for $25.00 and test the oil pressure yourself:

http://www.harborfreight.com/engine-...kit-98949.html

You might be able to buy the oil pressre test gauge kit for even less if you look in some of the car magazines, Reader's Digest or one of the other magazines where Harbor Freight puts their 20% off coupons. There are probably coupons online too, or you may even find a good deal on a test gauge from Amazon.com or one of the other tool websites.

Just my 2 cents.

Jimmy