Author Topic: Oil Pressure Question  (Read 309 times)

Offline cv70chall

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Oil Pressure Question
« on: August 03, 2018 - 02:29:33 pm »
Recently installed an oil pressure gauge. Has worked well. Averages about 30-40psi at idle. Ramps up to 40-60psi during driving. I've recently noticed that the pressure has been running higher while driving- say, around 70-80psi, although it drops to 30-40psi at idle.
Does this indicate I might need an oil change? I barely drive the car- maybe 100 miles a month.

?




Offline 70chall440

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Re: Oil Pressure Question
« Reply #1 on: August 03, 2018 - 03:04:03 pm »
That shouldn't indicate a need to change the oil. Oil viscosity can have an effect on pressure but dirty v clean of the same oil typically does not show a huge difference. Is this a mechanical or electrical gauge? Either way, I would suspect the gauge or sending unit. That said, you can always change the oil and see what happens to the pressure, can't hurt.
Current Mopar
70 Challenger RT 440-6, 73 Cuda (under const)
05 Durango, 99 Dakota, 01 Ram 4x4, 14 2500 4X4, 10 PCP Challenger RT, 01 Viper GTS ACR, 52 B3B w/330 Desoto Hemi, 70 Hemi RR, 61 Jeep FC170
Past Mopars
9 x Challengers. AAR Cuda, 4 RR, 2 GTX, 4 Chargers, etc... (too many to list)

Offline 73440

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Re: Oil Pressure Question
« Reply #2 on: August 03, 2018 - 11:03:01 pm »
Time of day when driving , due to viscosity and heat , will affect pressure reading.
7 am I will have almost 40 psi for first mile or so, then settles down to 25 psi rest of day.
This is iin daily driver with 400,000 miles , so your readings will be different.
67 440
72 413 / 727
73 Barracuda w/ 68 440
65 Plymouth Fury III , I sold ,was my Nana's car till 92 yo.
51 Ford F1 239 Flathead, flipped , new cab , stolen
59 BelAir 283 4 door original patina
01 Chevy van 400,225 miles
06 Crown Vic Police Interceptor
75 HD Ironhead converted to RH shift
73 HD Ironhead
82 HD Ironhead
74 Norton 850
80 HD Shovelhead
80 Husqvarna WR 390

Offline 70chall440

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Re: Oil Pressure Question
« Reply #3 on: August 03, 2018 - 11:14:39 pm »
Time of day when driving , due to viscosity and heat , will affect pressure reading.
7 am I will have almost 40 psi for first mile or so, then settles down to 25 psi rest of day.
This is iin daily driver with 400,000 miles , so your readings will be different.

This situation is normal, the condition being described in the beginning isnt. It was running 40-60 cold and now is running 70-80 which to me indicates a gauge or sending unit issue; either it was stuck originally now has free'd up or it was correct originally and now the diaphragm or spring has weakened.
Current Mopar
70 Challenger RT 440-6, 73 Cuda (under const)
05 Durango, 99 Dakota, 01 Ram 4x4, 14 2500 4X4, 10 PCP Challenger RT, 01 Viper GTS ACR, 52 B3B w/330 Desoto Hemi, 70 Hemi RR, 61 Jeep FC170
Past Mopars
9 x Challengers. AAR Cuda, 4 RR, 2 GTX, 4 Chargers, etc... (too many to list)

Offline 73440

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Re: Oil Pressure Question
« Reply #4 on: August 04, 2018 - 07:40:12 pm »
Ah, I see said the blind man, I got it backwards when reading the first post.
67 440
72 413 / 727
73 Barracuda w/ 68 440
65 Plymouth Fury III , I sold ,was my Nana's car till 92 yo.
51 Ford F1 239 Flathead, flipped , new cab , stolen
59 BelAir 283 4 door original patina
01 Chevy van 400,225 miles
06 Crown Vic Police Interceptor
75 HD Ironhead converted to RH shift
73 HD Ironhead
82 HD Ironhead
74 Norton 850
80 HD Shovelhead
80 Husqvarna WR 390

Offline 70chall440

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Re: Oil Pressure Question
« Reply #5 on: August 05, 2018 - 12:32:37 pm »
I do it all the time..  :banghead:
Current Mopar
70 Challenger RT 440-6, 73 Cuda (under const)
05 Durango, 99 Dakota, 01 Ram 4x4, 14 2500 4X4, 10 PCP Challenger RT, 01 Viper GTS ACR, 52 B3B w/330 Desoto Hemi, 70 Hemi RR, 61 Jeep FC170
Past Mopars
9 x Challengers. AAR Cuda, 4 RR, 2 GTX, 4 Chargers, etc... (too many to list)

Offline cv70chall

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  • 1970 Challenger
Re: Oil Pressure Question
« Reply #6 on: August 21, 2018 - 09:02:03 pm »
So, this is a mechanical gauge. I checked the line for kinks, etc and found none. The Engine has maybe 67k on it total before I installed it. All I've done is new cam, new heads, gaskets, water and oil pump- and this was nearly 3 years ago.
I drive the car maybe 30 to 80 miles a month..Yes...a month.
I've changed the oil twice since installing it.
Could I be using the wrong oil?
I'm currently using 10W40. It's in Florida.

Offline 70chall440

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Re: Oil Pressure Question
« Reply #7 on: August 22, 2018 - 11:47:38 am »
Swap the gauge.
Current Mopar
70 Challenger RT 440-6, 73 Cuda (under const)
05 Durango, 99 Dakota, 01 Ram 4x4, 14 2500 4X4, 10 PCP Challenger RT, 01 Viper GTS ACR, 52 B3B w/330 Desoto Hemi, 70 Hemi RR, 61 Jeep FC170
Past Mopars
9 x Challengers. AAR Cuda, 4 RR, 2 GTX, 4 Chargers, etc... (too many to list)