SSeric

So this might be a stupid question but am I understand this install correctly? Here's how I am understanding it.

1. Mount external cooler to bottom of frame, or anywhere that it will get airflow.
2. Take the two hoses that run into the stock PS heater and run them to the new cooler.
3. Replace upper radiator hose with one that is all rubber.

Is that correct? or am I not understanding this install correctly?

RebelExtrm02

iTrader: (3)

Correct.

SSeric

Cool thank you. I just discovered that PS fluid has been leaking into my radiator, so now its time to do this mod and a complete flush using Formula 88.

RebelExtrm02

iTrader: (3)

Make sure you flush out the power steering system too. If you have ps fluid in your radiator, you have coolant in your ps system as well. Buy two quarts of ps fluid for the flush. I didn't buy enough when I did mine and ended up having to do it over again once I bought more. It's cheap insurance to make sure you do it right the first time. You'll be surprised how nasty the ps system will be and quickly the fluid will shoot through it.

wssix99

iTrader: (5)

This is not correct in that the rail cooler DOES NOT need forced airflow over it. The rail cooler pictured at the start of this thread is a passive cooler and through the wonders of physics, it will create its own convection currents. The fins are also very fragile, so you don't want them in a place where debris can hit them.

If you want to have forced air moving over a transmission cooler, that is detailed in another thread, also linked at the start of this one.


In theory, yes. But you'll have to replace the hose that runs from the cooler back to the pump reservoir as the existing one is molded and won't be long enough.

SSeric

Well I got the type of cooler that LS6427 showed pictures of which isn't one of those really long rail coolers. And as far as replacing the return line back to the reservoir, I can just use a barbed male to male fitting with some band clamps and just add tubing to the end of it to make it long enough to reach the cooler right?

raysadude

iTrader: (11)

Just got mine done. Thanks OP and ls6427

IMO they should come out from factory like this

Xtreme57

iTrader: (6)

Going to do this mod next weekend. BUT no one has listed the part number for the upper radiator hose. Is this the right one?

wssix99

iTrader: (5)

Power STeering Pressure Hose - AC Delco 36-363170
Power Steering Return Hose GM 26068527
Upper Radiator Hose w/o Cooler GM 10271554

Xtreme57

iTrader: (6)

THANK YOU!!!!! All three of these are needed for this mod I take it?

Xtreme57

iTrader: (6)

Can I reuse the current PS pressure hose as well as the PS return hose if there is nothing wrong with them? Obviously I need to replace the upper radiator hose w/the non-cooler version in order to get rid of the stock PS cooler junk, but the other two hoses should be able to be reused, no?

wssix99

iTrader: (5)

No, you don't need to replace them - in particular the return hose.

I highly recommend doing the pressure hose, though. They don't last very long and are notorious for leaking. Its a lot easier to replace when you have the system apart and drained vs. in an emergency situation. (Those make a real mess!)

Xtreme57

iTrader: (6)

Just want to make sure this is the right hose -- AZ and other stores don't seem to go by the GM part number for some reason

http://www.autozone.com/autozone/par...530_10495_3492

RPM WS6

iTrader: (3)

This has been on my list of things to do, I've been putting it off and so far have been lucky and don't have any cross-contamination yet. I need to get this done an stop pressing my luck though.

Anyway, I'm going to go against the trend and just delete the factory cooler without installing an aftermarket one. My '98 did not come with any sort of cooler, but my '02 did. I've observed that the PS fluid in my coolerless '98 runs similar temps as the fluid in my '02 with the stock cooler and stock fan settings. I think the only way that the factory cooler is actually cooling the fluid is if:

- you have fan settings and a t-stat that keep your coolant significantly cooler than the stock t-stat and fan settings would normally allow.

- you autoX/road race/otherwise operate the steering system under severe conditions and/or very hot outside temps that allow the fluid to reach temps well beyond the stock coolant temps.

This post seems to be consistant with what I have noticed as well....

....very little difference in fluid temps between the stock cooler and no cooler at all. I have never had a boil-over condition with the coolerless '98 OR the stock cooler '02, and both have their original PS pumps with the bigger 275/40 tires on 17" wheels. It doesn't get as hot here in IL as what you guys in the south and southwest have to deal with, so maybe this is a bigger concern for you.

For my region and style of driving with this car (which involves basic daily driving with no competitive/extreme conditions), I don't think I really need an external cooler.

Having said all that.....it appears to me that the stock rubber lines that lead to the stock cooler are somewhat pre-molded with certain bends for the stock routing. Has anyone had any difficulty with kinking and such when routing these factory hoses in a different direction? My plan is to just plug the rubber line comming off the rack directly into the reservoir, trimming it down if necessary.

wssix99

iTrader: (5)

Did you read the GMHTP article linked in the first few posts? They did a good job explaining the rationale behind GM's move to the cooler and how cooling keeps the pump from wearing out as quickly.


Remember that the stock cooler is situated at the outlet of the radiator. The steady state temperature of the coolant coming out of the engine is 210* and the temperature of the coolant coming out of the radiator(and through the stock cooler) is much less.

Even if the radiator outlet temps were at 210, that's still cooler than the P/S fluid gets going through its system.


It doesn't look like those temperatures are accurate. I measured stock cooler temperatures much lower than that. If the person taking the measurements let the car sit for a few minutes and measured at the reservoir, its not a stretch to see how the reservoir (sitting next to a 210* engine) would heat up to match the engine temperature.


I've had major problems with this in Chicago - but with inner-city driving. More steering at lower speeds probably heats things up a lot more than higher speed driving with fewer turns.

I also have another theory that doing regular P/S fluid flushes will also help and combat the overflow problem just as well as a cooler. It seems that the overflows are worse for people with more miles on the fluid.


The only molded line is the stock cooler-to-reservoir line. If you toss that one, the stock return line should hook up to the reservoir with no issues.

RPM WS6

iTrader: (3)

Actually I feel that the article did a very poor job of explaining this. All it says about this is the following:

Under what conditions were premature failures so "notorious"? There was no recall for this, nor do I even remember seeing any TSB. I think words like "notorious" are better used for issues such as bubbling sail panels or power window motors. My '99 Z28 did not have a cooler, and never burned up a pump. My '98 Z28 also does not have a cooler, and still has it's stock pump after 15 years without any issues. Granted, the '98 is a very low mileage car, but the only times I *do* drive it are on warm/hot summer days around a crowded city and the pump is fine with no boil-over or noises after all these years.

The coolant can get hotter than you might think. With stock fan settings, coolant temps can reach as high as 235°F before the fans will engage high speed. At that point, cooled coolant coming *out* of the radiator will still be quite hot. You might be seeing "210" on your stock gauge, but a scanner will verify that anything between about 185° to 235° will show roughly "210" on the dash.

That poster stated that the readings were taken after 7 runs at a Auto-X event, which would explain the higher temps than you would have observed in normal driving conditions.

Either way, I've seen little difference in reservoir temps between my coolerless '98 and stock cooler '02. To be honest I ran that test a long time ago and don't recall the exact data, but I do clearly remember that the difference was marginal under my specific driving conditions, and since the pump in my '02 has 104k miles on it without failure while running at temps comparable to the coolerless pump in my '98, I just don't see this as a significant concern for my driving style and climate.

This makes sense. I've always made it a habit to change out some of the PS fluid on a regular basis, so that fresh is always being mixed into the system. Perhaps this is why I'm not seeing some of the issues that others have seen with more neglected systems.

Excellent, this is what I plan to do then.

wssix99

iTrader: (5)

Probably 10 or more P/S pumps returned under warranty the first year. lol I had a similar thought when I read the article. To make the change in the first year on an issue related to longevity, GM must have seen something odd and figured the cooler was more of an insurance policy vs. a "fix."


That's a good point. The conditions on the stock cooler would be highly variable. Under normal steady state conditions, I was measuring 185* but the temps can only go up from there.


Before I changed my cooler, I did measurements and didn't see a big difference, either - but this mod did just a bit better.

RPM WS6

iTrader: (3)

FWIW, the only "premature" issue that I've ever had with any LS1 PS pump was on my '00 WS6 when it was just 3-4 years old. It had the factory cooler, and revised fan settings that kept the coolant below 200° under all conditions. Shortly after installing an aftermarket cam (and revving the engine as high as 65-6600rpm on a few occasions), I noticed that the pump would whine at mid-range rpms during moderate acceleration from a stop light. And that car had headers/ORY and a decently loud exhaust, but the whining was still loud enough that I could hear it.

Over the years I've read about others that have had pump issues shortly after raising their shift points/rev limiter above stock. Might be caused by a combination of heat and old fluid that is then exposed to higher-than-designed rpms.

As for my '02, the pump does make some noise on a cold start when outside temps are below ~15°, but the noise goes away in a few seconds and the pump operates fine. No issues at all when outside temps are warmer. With 100k+ miles though, I don't fault it for making a bit of noise on a super cold morning.

Xtreme57

iTrader: (6)

Hey guys, so I just got this mod done with little issue. The only problem I came across was when I connected the new hose from the reservoir to the cooler (hose was supplied with my cooler), I started it up and noticed PS fluid started to seep out just a little bit from where the hose connects to the bottom of the reservoir. I can't tighten the band clamp on it any more, and I can't get the hose any higher up the PS reservoir connector. Any suggestions on how I can stop this damn leak?

Xtreme57

iTrader: (6)

Does anyone know what size the reservoir to cooler hose is? 5/8" or 1/2"? I think the hose I got MIGHT just be slightly too small, which would explain why I can't get it all the way up the reservoir spicket ...