smitty2919

Buy Redline PS fluid and stop guessing.

King Nothing

iTrader: (9)

Already have it in the garage, still need to finish front suspension and install belts before I mess with the power steering.

wssix99

iTrader: (5)

(I missed that detail above.)

Sure - the pump could also be ruined. I'd call Turn One and see what they think.

I've seen reasoning on doing this because both P/S fluid and Trans fluid are "hydraulic fluids", so they must be interchangeable. By that reasoning, motor oil and baby oil (both "oils") should be interchangeable, as well.

I understand trans fluid is a lighter weight fluid and also has other chemicals/detergents in it.

King Nothing

iTrader: (9)

That would suck if it was ruined, 5 years old and less than 2500 miles on it. I'll find out soon enough.

joecar

I doubt ATF could ruin the PS pump (auto trans is much more delicate than PS system)...

ATF does have the problem that some of its additives break down at higher temperatures... but PS fluid probably has the same problem, IDK for sure.

smitty2919

If I have learned anything while autocrossing my car for the past 3 years, is that you don't mess around when it comes to fluids.

Mobil 1 5w-20 synthetic (I think that's stock weight oil) is JUNK when you almost hot lap a car in 90* heat with your wife...I saw 5psi hot idle...switched to Redline 10w-40 and I see no less than 25psi hot idle.

Same goes for power steering fluid and a proper cooler...the $30 fin and tube coolers are more of a restriction than they help cool. Putting one on a street car is more of a conversation piece to say you have one. Many that race run a B&M stacked plate cooler with 1/2" inlet/outlets for no restriction and good cooling. Redline fluid keeps pump from whining and doesn't break down at higher temps.

Same goes for quality brake fluid...

King Nothing

iTrader: (9)

5w-30 for LS1's and if your only at 25psi at hot idle you have issues and shouldn't be pushing the engine . . . that's an LS1 though, maybe an LT1 is ok running at that. Currently mine sits at 22psi when hot and I won't dare put it on a autoX course until I have the engine looked at, I think I have worn bearings.

Doesn't the position of the cooler also help how much it cools? That's why I put mine on the face of the condenser as opposed to under the radiator support. I plan to autoX the car and will have to keep an eye on this and my end up putting on the other cooler to see which one is better.

LS6427

iTrader: (2)

Any cooler thats actually leaning up against the condensor just causes a hot spot on the condensor and then onto the radiator......thats the same size as the cooler.

My tranny cooler is 3 inches away from the condensor......lets it mix with ambient ram air before that hot air off the cooler goes into the condenser/radiator.

.

RPM WS6

iTrader: (3)

Yes, factory fill (and recommendation) for the LS1 was 5w30, not 5w20.

The older SBCs do tend to run a bit lower oil pressure at idle. However ~25psi at hot idle in warm ambient temps, especially after some aggressive driving and/or with extra load on the engine (such as A/C), doesn't specifically indicate a problem - even more so for an auto car (which has a 30% lower stock idle speed in gear than an M6) with the older LS1 pump (meaning 2000 or earlier.) Of course, oil grade will also play a role in this. Personally, I don't know why some folks use hot oil pressure at idle as a primary indicator of engine health - the more important information is how oil pressure behaves as engine rpms rise. Not to mention the fact that the factory gauge and sending unit aren't exactly known for rock solid reliability.

smitty2919

I'm not worried about 25psi at a 700rpm when oil temps are 215* and coolant temps are about 180-190* idle. I go by 10psi for every 1000rpm rule.

My point was Mobil 1 synthetic 5w30 is fine for daily driving, not for racing situations. Come "off season" I switch back to Mobil1.

For PS fluid I'll run Redline all the time.

King Nothing

iTrader: (9)

So all the LS engines from the factory sitting at 40-45PSI when at OT are not in theroy operating better than the engines with only 20-25PSI? If I pull my engine apart which I might, I'll let you know if my bearings are worn causing the low oil PSI.
10 PSI is the factory minimum requirement, I personally wouldn't drive a vehicle that has 10psi at idle . . . or in theroy at idle it would be 7-8PSI. But that's just me. Do you run 1/2 qrt more than your engine takes to take into account the sloshing around of the oil and preventing cavitation?

kingtal0n

iTrader: (1)

I enjoy using ATF because I like to have a manual trans car that leaks ATF. Don't try to take that away from me?

No, not really the same reasoning. Motor oil is mostly long chain hydrocarbons, with modifications to improve stability under variety of conditions. Prolonged exposure may cause DNA modification which could lead to cancer or other issues.

Baby oil on the other hand, is designed for human contact. I have no idea what is in it, but it probably isn't long chain hydrocarbons missing functional groups with modifications for stability under a variety of conditions.

I am fairly confidence PS fluid can be exchanged with ATF. AFT might even keep the PS system cleaner, just a guess though.

smitty2919

At a minimum I make sure oil is topped off 100% if not adding 1/2qt more.

I blame the Mobil1 because ALL I did was switch Redline 10w40 along with a oil temp gauge where the Low Oil Level sensor is due to it leaking. And I no longer have oil pressure issues when racing.

Maybe Mobil1 and a good oil cooler setup will be a different story, but when all I have to do is switch oil, why add all the cost/complexity/piping/mounting of a cooler setup if I don't have to. Road racing will be a different story.

King Nothing

iTrader: (9)

International model 8100 trucks have a cooler sitting against the Condensor and their A/C works correctly and I highly doubt condensors have failed due to this. That air dam serves a purpose, it draws the air up to cool the radiator, so but cutting a long hole in it you are not efficiently or correctly cooling the radiator in that exact spot.

RPM WS6

iTrader: (3)

No, this is not necessarily a direct indication of a healthier engine. First, let's get back to basics...

Which factory stock LS1 engines have you seen at 40+psi at hot idle? Where they:

- M6 cars? (remember, 30% higher engine rpm vs an auto idling in gear - so they should show noticeably higher readings)

- 2001-'02 cars? (these had an LS6 pump stock, which always showed higher pressure vs. same idle speed in a '98-'00 car)

- What grade/brand of oil were in these engines?

- How hard had they been run prior to you observing these readings?

- Was the A/C running? (additional load)

- What were the ambient temps? (even with a properly functioning cooling system, hotter ambient temps still have some effect)

- How many miles on those engines?

The answers to these questions can significantly effect just what those idle readings may (or may not) indicate in terms of an issue. Again, what really matters regarding engine health is how the oil pressure behaves as engine rpms rise. If pressure is low at idle, this could be because of oil grade choice, a failing sending unit, a dying oil pump, a pick-up tube O-ring issue, or even a problem with the gauge itself. This single factor alone is not a reliable primary or direct indicator of engine health, period - and a "normal" reading for a stock 2002 M6 car is not exactly "normal" for a stock 2000 A4 car, for the reasons explained above.

I've personally owned four LS1s in four different cars, all were automatics. My '98, '99 and '00 cars ALL showed 25-30psi in gear at hot idle with the stock pump and stock idle speed, especially in hot ambient temps and/or with the A/C running. I bought the 1999 and 2000 cars brand new, and this is how they were from the beginning. My 2002 car showed 35-40psi under the same conditions, likely due to the stock LS6 pump.

Over a period of several years, I modified the 2000 car extensively. Before doing a cam/oil pump upgrade I bumped the idle speed to that of an M6 car (800rpm), and hot idle oil pressure increased by about 5 psi under otherwise same conditions (went from 25-30 to 30-35.) Later, I added an upgraded oil pump and saw a further jump to about 45psi at hot M6 idle rpms in gear. At this point the engine had only about 7,000 miles on it, and it hadn't been rebuilt, so those changes in pressure were entirely the result of idle speed and the oil pump itself, not bearing heath.

My current '98 is a limited use show vehicle with under 18k miles. It's an auto with stock tuning and a completely stock internal engine. It continues to make 25-30psi of oil pressure at hot idle in gear after long drives in warm ambient temps, just as it has for the 13 years I've owned it.

If you are seeing other alarming things (such as a quick drop in pressure when you raise engine speed) in addition to your idle pressure readings, then you might have cause for concern. Or if the engine is only making 25-30psi of idle pressure on a cold start, and you've already verified that the sending unit and gauge are accurate. Otherwise, ~25psi of idle pressure with a stock 2000 or earlier LS1 pump at stock A4 idle speeds is not, by itself, necessarily an automatic indication of a serious problem - especially if the engine has some miles on it.

wssix99

iTrader: (5)

Fair - I've always felt a little weird about this...


I understand they are close in properties but still different. Since the pump builder for the poster at issue is TurnOne, the answer as to what should be used can be easily gotten. They actually have a FAQ that recommends to use P/S fluid: https://www.turnone-steering.com/blo...r-steering-faq

Maybe they can chime in as to why or someone can place a call?

kingtal0n

iTrader: (1)

You want to know why somebody is recommending PS fluid for a PS pump?

let me take a wild guess: because its the cheapest thing that will work and is safe to use?

steering_experts1

We recommend a full synthetic name brand power steering fluid. Transmission fluid doesn't have anti-foaming agents in it like power steering fluid does. Transmission fluid can foam and cause cavitation, which could lead to the pump sucking air.

Thanks,
​​​​​​​Junior

joecar

Out of curiosity, I searched the www and I do not see any Mobil 1 PS specific fluid...

I did see in various places where Mobil say to use M1 ATF for PS...

I also looked up what M1 ATF contains, and it contains anti-foaming agent (which makes sense since why would you want your trans to suck air/foam).

smitty2919

TurnOne....let people run ATF in the PS system...just more business for you when they screw their **** up and you get to rebuild it! Yay

My PSC pump (bought used but NIB) with B&M cooler and stock reservoir HATED even Autozone brand fluid. I used it to make sure of no leaks and everything worked....I would drive around the block and it would whine. Switched to Redline fluid and I barely get a hint of whine at autocross running 315 hoosiers, getting 5 runs at 70-80* day.