Radiator transmission cooler as power steering cooler?

[4x4_Welder]

Truck is a 71 F250 body on an 85 F250 chassis with an 89 7.3IDI and ZF 5speed.

The typical Ford power steering "cooler" loops on the front crossmember is in rough shape. I'd also like to mount my electric lift pump right where that cooler is. I put a new radiator in this thing, and it has a trans cooler that won't be used with this manual, so what is the feasibility of using that internal cooler for the power steering? It should be less pressure than a trans cooler, and should flow enough as far as I know, but can anyone provide any kind of verification on this? It just seems like the easiest option, and cheapest.

 

[I Lean]

One of the functions of an in-radiator trans cooler is to WARM the ATF to get it to operating temp more quickly. I don't think you'd necessarily want the extra heat in your power steering system? It seems like cooler is better for that, to a point.

Maybe.

 

[TurboMinivan]

I, too, will vote for not running your PS fluid through the radiator's in-tank cooler, for the same reason.

Good news: based on what I've seen on various OEM vehicles, a PS cooler can be very, very small. You could either go to AutoZone/O'Reilly/etc and buy the smallest generic trans fluid cooler they have, or perhaps go to a wrecking yard and remove one from whatever random vehicle you find.

 

[I Lean]

I, too, will vote for not running your PS fluid through the radiator's in-tank cooler, for the same reason.

Good news: based on what I've seen on various OEM vehicles, a PS cooler can be very, very small. You could either go to AutoZone/O'Reilly/etc and buy the smallest generic trans fluid cooler they have, or perhaps go to a wrecking yard and remove one from whatever random vehicle you find.

Agreed.

This is the one I'm running on my Cruiser--it came off an Expedition from a junkyard.



Mounted behind the grill:

 

[N-Smooth]

Yeah those are like $20 at Autozone. I originally ran one of those but then upgraded to the big RV trans cooler for my power steering.

 

[4x4_Welder]

I do also have a cooler about twice the size of the pictured one kicking around, but that involves buying hose, mounting it, etc. I guess I can go that route, I didn't think the output side of the radiator would be that warm.

 

[N-Smooth]

Test it. I bet it warms more than it cools.

 

[TurboMinivan]

I originally ran one of those but then upgraded to the big RV trans cooler for my power steering.

Which raises the question, how cool does your power steering fluid need to be, anyway?

Side note: when I installed the 4L80E in my Grand Prix, I decided I wanted (a) a very large fluid cooler that (b) was not located in a radiator end tank. I bought the largest Hayden stacked plate cooler they make--part number 689, it measures 11" x 11" in core size and is designed 'for Class A RVs with GVWR up to 30,000 pounds, towing up to 10,000 pounds.' The plate and fin design is more efficient than the old school tube and fin style, so I figured I could get away without also running my trans fluid through the radiator. I made sure to mount my cooler out front where it would get lots of airflow--you can't tell from this photo, but it actually sits a few inches in front of the condenser:

To date, my trans fluid has never gone above 165^ even in the summer heat. This has made me very happy with this setup.

Back to power steering: I highly doubt a power steering pump generates as much heat as a 4L80E being fed by a big block 454. Therefore, I can only presume such a giant fluid cooler would keep your power steering fluid at ambient temperature at all times. There's no kill like overkill, I suppose.

 

[4x4_Welder]

When I was moving cross country, I was driving an 84 F250 with a straight axle swap and 35s, towing a trailer. I lost power steering just before crossing from Connecticut into New York, and found a plastic bag wrapped around the power steering cooler. This was about 100 miles into the trip (which also involved blowing the transfer case as I passed the "Welcome to Indiana" sign), and I'm running the same style pump on this truck.
So, these Fords do need some sort of cooler for the PS.

 

[Mouse]

I've used a smaller transmission cooler for power steering - it did just fine until I upgraded to hydro-assist. Then there was flow issues and the steering was unhappy. To solve that I ditched the trans cooler and went with the straight-through aluminum heat sink that PSC sells.

 

[4x4_Welder]

Well, I got my PS cooler installed today. Maybe some time this month I can find the time to mount the fuel pump, and maybe even start the damn truck!