A Couple of 2017 Tahoe Questions - Brakes & Oil Pressure

[Plimbob]

I may have mentioned in one of my previous posts that I purchased a theft recovered 2017 Tahoe LT with 77,000 miles on it a month or so ago. I have repaired all the damage and actually drove it today for the first time today to get it inspected.

It ran fine for the most part except for two things:

1. Seems like the oil pressure is a shade low at 70 mph it is about 42-43 and at idle about 28-30. I say this because my 07 Tahoe 5.3 pressure at 70 is approx 50-55. Is the 42-43 at 70 mph normal for the newer engines?

2. Coming back home I stopped at the gas station and was waiting in line idling for about 5-8 minutes and all of a sudden the brakes seemed to get very stiff to push and weren't stopping well. I went ahead and pulled up to the pump when it came time.

When I started it back up the brakes seemed fine. I pulled over in the lot, checked things out underneath and under the hood nothing seemed out of the ordinary.

I started it back up pumped the brakes and they seemed normal and took the back way home just in case and had to stop various times and they seemed normal?

Any feedback on these two issues would be appreciated.

Thanks,
Tim

 

[Plimbob]

I may have mentioned in one of my previous posts that I purchased a theft recovered 2017 Tahoe LT with 77,000 miles on it a month or so ago. I have repaired all the damage and actually drove it today for the first time today to get it inspected.

It ran fine for the most part except for two things:

1. Seems like the oil pressure is a shade low at 70 mph it is about 42-43 and at idle about 28-30. I say this because my 07 Tahoe 5.3 pressure at 70 is approx 50-55. Is the 42-43 at 70 mph normal for the newer engines?

2. Coming back home I stopped at the gas station and was waiting in line idling for about 5-8 minutes and all of a sudden the brakes seemed to get very stiff to push and weren't stopping well. I went ahead and pulled up to the pump when it came time.

When I started it back up the brakes seemed fine. I pulled over in the lot, checked things out underneath and under the hood nothing seemed out of the ordinary.

I started it back up pumped the brakes and they seemed normal and took the back way home just in case and had to stop various times and they seemed normal?

Any feedback on these two issues would be appreciated.

Thanks,
Tim

Update to point #2
After some further research I determined there is a recall on a braking problem that fits what I experienced. I am going to give my local Chev dealer a call and try to get that resolved. For anyone else experiencing low speed braking problem here is the recall overview:

Manufacturer Recall NumberN192268490
NHTSA Recall Number19V645

Summary- General Motors has decided that a defect which relates to motor vehicle safety exists in certain 2014-2018 model year Cadillac Escalade, Chevrolet Silverado, Chevrolet Suburban, Chevrolet Tahoe, GMC Sierra, and GMC Yukon vehicles. In some circumstances, these vehicle may have a condition in which the engine-mounted mechanical vacuum pump output may decrease over time, decreasing the amount of vacuum/power brake assist.

 

[OR VietVet]

Yep, sure sounded like power assist problem. Great that there is a recall for it. Sounds like a new vacuum pump is in your future.

As for the oil pressure. Do an oil pressure test and replace the sender when you have it off. Post the pressure results back here.

https://www.rockauto.com/en/moreinfo.php?pk=6312810&cc=3434402&jsn=2242 aftermarket only listed at RA but here is the AC Delco one at Amazon with free shipping.

https://www.amazon.com/ACDelco-1263...ild=1&keywords=12635397&qid=1587495093&sr=8-2

 

[Plimbob]

Yep, sure sounded like power assist problem. Great that there is a recall for it. Sounds like a new vacuum pump is in your future.

As for the oil pressure. Do an oil pressure test and replace the sender when you have it off. Post the pressure results back here.

https://www.rockauto.com/en/moreinfo.php?pk=6312810&cc=3434402&jsn=2242 aftermarket only listed at RA but here is the AC Delco one at Amazon with free shipping.

https://www.amazon.com/ACDelco-1263...ild=1&keywords=12635397&qid=1587495093&sr=8-2

Thanks Ron for the info. I had to replace the one on my 07 a year or so ago and it was real PIA!. I don't know if Chev could find a harder place to get to! I assume the 2017 are in the same location...

Tim

 

[OR VietVet]

Thanks Ron for the info. I had to replace the one on my 07 a year or so ago and it was real PIA!. I don't know if Chev could find a harder place to get to! I assume the 2017 are in the same location...

Tim

So, now you have something to look forward to. You did it once and can do it again.

 

[avalonandl]

These newer LS engines do not have high oil pressure with variable pressure pumps. Yours seem fine.

My LT1 which is a DI engine in my 2017 Camaro SS runs at 35-45 psi all the time. Lower at hot idle.

These new synthetic/Dexos oils are amazing and provide all the lube you need.