PSI differential on oil filters

[TheLoneRanger]

Does anyone have an idea of what the restriction on the average spin-on oil filter would be? I don't mean the pressure at which the bypass valve opens, just the PSID across the filter media (with ATF flowing through).

I'm researching add-on transmission fluid filters, and am concerned about the possible restriction an extra filter might cause.

Thanks for all opinions.

 

[S2000driver]

I would be very interested in seeing dynamic pressure differentials for different filters at high demand and over time. To simulate time, measured particulates could be added to the oil at a constant rate.

I would expect the pressure differential to start small and grow larger to the point that the bypass kicks open. Yes, I want to see where things level off when the bypass valve opens.

 

[Ken2]

Mr. Hugo Brizuela of Parker (parent company of Racor) emailed me that the pressure differential across their full-flow Racor LFS 22825 transmission filter with warm ATF was 0.25 psi. This is a 6 micron absolute (98.5%) filter. $81...email me for a source. I do not know of any full flow oil filters that filter this fine.

I asked Champion Labs about using their Mobil 1 filters for a transmission, and they do not recommend the filter for that application.

Baldwin recommended their B252, B163, or BT5 which are 22 micron, and which fit a 3/4-16 filter head which I'd part with cheaply. Baldwin said that their B260-10 has a 9 micron rating but no bypass valve and a 1-1/8 - 16 thread (hard to find a filter head).


Ken

[ February 02, 2003, 12:27 AM: Message edited by: Ken2 ]

 

[unDummy]

Various filters have different restrictions.

It all depends on FLOW RATE.

At what flow was the .25psi pressure drop?

What is the flow of the ATF pump in your vehicle?

What thread size is your ATF filter kit and where is it installed(tap into cooler lines?)?

If choosing a name brand ATF filter kit, I wouldn't worry about filter choice. Use what they recommend.

 

[NewGTO]

Here is a small chart of pressure drop across a oil filter FL400S on remote oil filter adapter
with 3/8 lines.
Oil Temp. GPM Gallons per minute, Psi inlet/outlet

OIL FILTER Pressure drop Free Flow.
ATF Trans Oil Mercon V Filter:Motorcraft FL400S

81 ^F 85 ^F
1.5 gpm 2 gpm
20 psi 25.5 psi
17.5 psi 20.5 psi


100 ^F 102 ^F
2 gpm 1.5 gpm
21.5 psi 15 psi
16.5 psi 11.5 psi

127 ^F 129 ^F
1.5 gpm 1 gpm
11.5 psi 7.5 psi
8.5 psi 6 psi

135 ^F 150 ^F
2 gpm 2 gpm
15.5 psi 14.5 psi
12.5 psi 11 psi

152 ^F 152 ^F
1.5 gpm 1 gpm
10 psi 6.5 psi
7.5 psi 4.5 psi

165 ^F 175 ^F
2 gpm 2 gpm
14 psi 13.5 psi
10.5 psi 10 psi

176 ^F 176 ^F
1.5 gpm 1 gpm
9 psi 6 psi
6.5 psi 4.5 psi

180 ^F 200 ^F
2.5 gpm 2 gpm
18 psi 12 psi
14 psi 9 psi

200 ^F 201 ^F
1.5 gpm 1 gpm
8 psi 5.5 psi
6 psi 4 psi

205 ^F
2.5 gpm
17 psi
12.5 psi

 

[TheLoneRanger]

NewGTO, that's an interesting chart, thanks. I would expect those differential figures to be about right, but I wonder at what RPM the pressures were taken? This chart must be for idle pressures, because I think the pressures would be much more at higher RPM's, such as 3000.....