Oil Coolers

[2000StreetRod]

Begin Lessons Learned

To save you the time of reading this long thread and to prevent you from duplicating modifications that were later determined to be undesireable I've added this section.

General
1. Remote oil filters and coolers can increase engine and transmission life by reducing oil particles and maximum fluid temperatures but may also reduce reliability due to additional plumbing. Flexible hoses are easier to work with than rigid tubing but are heavier, have lower temperature and pressure specifications, larger minimum bend radius and deteriorate with age. Hoses routed near exhaust components should be protected with heat resistant sheathing. Hoses in contact with abrasive surfaces should be protected (I used larger diameter heater hose). Hoses with short bend radius should be reinforced to prevent kinking (larger diameter heater hose). Push-loc/twist-lok) hose with hose clamps increase reliability. Perforated hose clamps damage hoses. I used fuel line hose clamps on 3/8 inch internal diameter ATF hoses and non-perforated stainless steel hose clamps on 1/2 inch internal diameter engine oil hoses. Components should be installed where they are damage protected from off-road hazards and hydraulic lifts. Most of my components are mounted behind the bumper and front grille and hose runs to the engine and transmission are above the bottom of the frame.
2. Brass fittings are fairly expensive (>$200 for my installation) and heavy. Thoughtful planning and selection of the optimum remote filter adapter configuration (2 ports vs 4 ports, vertical vs horizontal ports, left vs right ports) can significantly reduce the number of fittings. Flare (AN) type fittings are also fairly expensive but weigh less than brass fittings. Pipe threads should be sealed with Teflon tape or thread sealer. I experienced leaks with Teflon tape and eventually used high temperature thread sealer on all pipe threads. Flare fittings are subject to loosening from vibration. There are wire locks on my thermostat -12 O ring to -08 AN male adapters. I used thread lock on the other AN fittings.
3. For accurate readings oil temperature sensors should be mounted horizontally or inverted to prevent air pockets and where oil flow is not stagnant.

Engine oil cooler
1. An engine oil cooler without thermostatic control should not be installed (especially in cold weather climates). The engine oil should reach optimum temperature as soon as possible for better lubrication, reduced friction (better fuel economy and power) and sludge reduction. The optimum engine oil temperature is high enough to eliminate water vapor (> 212 Deg F) while low enough to prevent breakdown. I used a 215 degrees F. thermostat from Canton Racing.
2. The engine oil should not be routed thru the radiator internal oil cooler. According to my remote reading temperature sensor even in warm weather the temperature of the radiator oil cooler is less than 150 degrees F.
3. If an Accusump is incorporated a check valve should be installed in the return oil path to direct oil from the Accusump only into the block adapter inlet.


ATF oil cooler
1. The 5R55E transmission has an internal thermistor that provides the PCM with transmission fluid temperature (TFT). The PCM uses the TFT to determine whether cold start shift schedule (quicker shifts) is necessary. The PCM also adjusts EPC pressure for TFT. The 5R55E also has an internal thermostat that opens the external cooling loop when the torque converter temperature reaches 150 degrees F. Ford apparently has determined that 150 degrees is optimum. Some members modify the valve body to permanently keep the external cooling open defeating the benefits of the design.
2. Best ATF cooling is achieved by routing the transmission external cooling loop output to the radiator internal oil cooler and then to external air coolers and back to the transmission. Even though in summer the temperature of the radiator cooler is typically greater than ambient air temperature, liquid to liquid heat transfer is many times greater than liquid to air heat transfer for a specific temperature. Auxiliary coolers are mounted in front of the radiator and encounter cooler air than the radiator and A/C condenser. If the radiator coolant exceeds 150 degrees F then the auxiliary coolers can lower the ATF temperature. There is no concern during cold weather operation that the ATF temperature will be too low because the transmission internal thermostat will not allow flow thru the external cooling loop if the temperature is less than 150 degrees F. Auxiliary coolers (excluding the radiator cooler) should be in parallel to reduce flow resistance.

End Lessons Learned

I recently read several threads regarding transmission oil coolers. I was thrilled to learn that my 5R55E internally recirculates the transmission oil until it reaches operating temperature. It is only after the operating temperature is achieved that oil is allowed to flow to the external cooler(s).

I also did some internet research on engine oil coolers and the importance of maintaining the optimum oil temperature. I remember that my 1964 Alfa 2600 Spider had an external temperature controlled oil cooler and decided I want something similar on my Sport. The optimum engine oil temperature appears to be 180 to 200 degrees F - about the same as the standard engine coolant thermostat.

So this is my idea.

1. Replace the stock oil filter with a remote engine oil filter/oil cooler engine block adapter.

2. Disconnect the transmission oil lines from the transmission oil cooler in the radiator.

3. Disconnect the transmission oil lines from the auxiliary transmission oil cooler mounted in front of the air conditioner condenser.

4. Route an engine oil line from the adapter outlet to the remote oil filter inlet.

5. Route an engine oil line from the remote oil filter outlet to the previously auxiliary transmission oil cooler inlet.

6. Route an engine oil line from the previously auxiliary transmission oil cooler outlet to the radiator internal previously transmission oil cooler inlet.

7. Route an engine oil line from the radiator internal previously transmission oil cooler outlet to the remote engine oil filter/oil cooler engine block adapter inlet.

8. Mount a large new transmission oil cooler in front of the air conditioner condenser.

9. Route transmission oil lines from the new transmission oil cooler to the transmission.

The results of the above should be:

1. Improved engine oil temperature regulation (reduced maximum) due to the external oil cooler.

2. Improved engine oil temperature regulation (increased minimum) due to radiator internal oil cooler.

3. Improved transmission oil temperature regulation (reduced maximum) due to increased capacity.

[2000StreetRod]

I've finally gotten started on my oil coolers/remote oil filters modification. I decided on a different configuration than previously described. As you can see from the photo below, I have an external transmission oil cooler in addition to the transmission oil cooler that is contained in the side of the radiator.

The lack of symmetry and the idea that one can never have too much cooling capacity with a thermostatically controlled system prompted me to purchase another used external transmission oil cooler identical to the stock one. My current plan is to route the transmission oil output to a full flow remote oil filter. The filtered oil will then be split between the two identical external coolers. The outputs of the coolers will then be combined and routed directly back to the transmission.

The stock engine oil filter will be replaced with a engine block screw on adapter. The adapter output will be split between a full flow remote oil filter and a bypass oil filter. The output of the full flow filter will be routed to an external oil cooler. It's output will be combined with the output of the bypass filter and then routed to the radiator oil cooler (previously used for transmission oil cooling). The output of the radiator oil cooler will return to the engine block screw on adapter.

The only place on my Sport that can accomodate all of this oil management equipment with fairly easy access to change the filters is behind the front bumper and grille.

The photo below shows one of the stock external transmission oil coolers and the location of the rivets for one of it's mounting brackets.

The rivets were easily drilled out using care not to go too deep and the bracket removed as shown below.

The bracket was removed because it is in the way for the new mounting location and it slightly blocks air flow.
The other stock mounting bracket is shown below.

Unfortunately, this bracket is flow soldered to the cooler and not removable. It only blocks a small quantity of air and may be useful when routing oil lines.

[CDW6212R]

Well Dale, you have been reading my mind again. I'm still mulling over routing combinations for my trucks, for both the oil and ATF. Get Amsoil bypass adapters and filters, buy the adapters separately. I got two simple bypass adapters for about $20 each, they have a heavy duty version for about $55 for just the adapter.

I'd like to regulate the ATF better for my V8 truck, and I'll have the two external oil filters and a pre lube pump. So I'll have the many lines up front also, I'm wondering what other thermostatically controlled adapters are available. The radiator heats ATF all the time under ideal conditions. I'm not ready yet to decide, I'll pay attention to what you find here. Regards,

[99SportX]

I have an extra stock external trans cooler and I was thinking of somehow reversing the mounting bracket and mounting it right next to the stock passenger side cooler. If you run them in parallel you cut your flow rates in half as well as reduce the restriction through the coolers which should double your cooling capacity

[CDW6212R]

I think his description was for that, I spent about $25 each for "Y" fittings from Jegs.

[2000StreetRod]

Originally Posted by CDW6212R

. . .Get Amsoil bypass adapters and filters, buy the adapters separately. I got two simple bypass adapters for about $20 each, they have a heavy duty version for about $55 for just the adapter.

I'd like to regulate the ATF better for my V8 truck, and I'll have the two external oil filters and a pre lube pump. So I'll have the many lines up front also, I'm wondering what other thermostatically controlled adapters are available. The radiator heats ATF all the time under ideal conditions. I'm not ready yet to decide, I'll pay attention to what you find here. Regards,

I found a source (tmvtaylor on eBay) for a threaded bushing with 1-16 outer threads and 3/4-16 inner threads ($16 includes shipping). It allows one to mount a Amsoil bypass filter on a standard full flow remote mount. I think tmvtaylor had thermostatic controllers. Also, Perma-Cool makes remote mounts with different inlet and outlet orientations. I have spent more than $100 in brass fittings. Much of that could have been saved if I had opposite side ports instead of my existing three up port remote filter mounts.

I purchased a Moroso check valve in anticipation of a future purchase of a pre-oiler. I haven't found any decent place to mount the 3 quart accumulators. I don't want a pump because it requires an oil pan pickup. I can find a place for an AMS Oiler but its expensive!

[2000StreetRod]

Originally Posted by 99SportX

I have an extra stock external trans cooler and I was thinking of somehow reversing the mounting bracket and mounting it right next to the stock passenger side cooler. If you run them in parallel you cut your flow rates in half as well as reduce the restriction through the coolers which should double your cooling capacity

My thoughts exactly! You'll see why I had to move the stock cooler when I post the explanation of the remote filter mounts.

[2000StreetRod]

I never have liked the process of mounting oil coolers by attaching them to the air conditioner condenser with plastic straps. So I purchased some aluminum (easy to cut and drill) angle stock and some 90 degrees angles from Lowe's. The cut pieces are shown below.

Then I attached the right angles to the angle stock as shown below.

The angles without attached right angles are the inside mounts and the others are the outside mounts. The extra 3 holes in each angle stock are for cable ties to wrap around each cooler. Below is a photo of the passenger side with brackets installed.

And then below is a photo of the driver side with brackets installed.

You may notice a short piece of flat aluminum partially under the upper end of the inside bracket. It was placed there to compensate for the angle of the center vertical support.

[CDW6212R]

The bypass filters don't have a restrictor in them, the restrictor is in the mounting adapter, it's less than a .100" hole. I also noticed that many adapters have the outlets at inconvenient angles. Summit and Jegs had a good variety.

FYI, your SOHC has two oil pans, and the lower pan is steel and easily removable. I'm planning to eventually add a couple of fittings to that on mine. My V8 truck will have the fittings installed in the pan before I swap the engine. I wish the Mallory 4030 pump was still available. Assuming it is reliable, it wasn't much over $120 when I got it, and it's smaller than the accumulators.

[99SportX]

I look forward to checking out the results!

[2000StreetRod]

Originally Posted by CDW6212R

The bypass filters don't have a restrictor in them, the restrictor is in the mounting adapter, it's less than a .100" hole.

Thank you for mentioning the restrictor. That has prompted another revision of my oil flow configuration. I suspect that the construction of a bypass oil filter is similar to that of a free flow filter. There is a valve in the filter that opens when the incoming flow exceeds the capacity of the filter. In a full flow filter this ensures that the engine will continue to get oil even when the filter is blocked. If a restrictor of small enough diameter is inserted in the oil flow prior to a bypass filter to prevent its flow capacity from being exceeded, then all of the oil flowing into the bypass filter will be filtered. The restrictor would also prevent the valve from having to open. The valve in full flow filters is probably designed for infrequent operation. I hope that the valve in the bypass filter is designed for frequent operation. In any case, the flow thru the bypass filter is proportional to the difference in inlet and outlet pressure and the resistance of the filter element. Since I want all oil to flow thru the full flow filter, I will route the oil from the engine block adapter to the full flow filter and then split the output of the full flow filter between the bypass filter and the added external engine oil cooler. The flow thru the bypass filter will then be dependent on the drop in pressure due to the restriction of the external oil cooler (small) and within the capacity of the bypass filter. So I don’t plan to utilize a restrictor. Below is a crude diagram of the engine oil flow.

The only place I'm considering so far to mount an accumulator is behind the front crossmember between the lower control arm mounting bolts. It's probably not a possible location for a 4 wheel drive vehicle. Also, the horizontal mounting would limit my accumulator choices.

Below is a photo of both sets of transmission cooler mounting brackets.

And below is a photo of the passenger side cooler showing the cable ties before they were cut off.

A disadvantage of my cooler orientation is that I can't gravity drain them. However, it was the only configuration that avoided the hood latch while maximizing airflow. Just ignore the large hole in the upper left of the photo. It's associated with another modification.

[CDW6212R]

I doubt that the bypass filters have a bypass valve in them. I think they are intended to only flow a very small percentage of fluid compared to the main flow. I am installing a dual filter system in my trans lines, and considered removing the restrictor for the bypass filter. In a transmission the fluid should be extremely clean anyway, so it wouldn't matter much, so I'll leave it as it was made for now.

The oil doesn't get too hot normally, which is why I think an oil cooler is rare. The ATF is more critical, and lowering those temps will help a lot. I think the radiator makes it hard to really lower ATF temps, so I'm interested in what numbers you get.

[2000StreetRod]

Originally Posted by CDW6212R

I doubt that the bypass filters have a bypass valve in them. I think they are intended to only flow a very small percentage of fluid compared to the main flow. . . .

The oil doesn't get too hot normally, which is why I think an oil cooler is rare. The ATF is more critical, and lowering those temps will help a lot. I think the radiator makes it hard to really lower ATF temps, so I'm interested in what numbers you get.

I plan to e-mail Amsoil and ask about how their AMS Oiler works. I'll also ask if their bypass filter includes a bypass valve.

The 1964 Alfa 2600 Spider I owned long ago came standard with a thermostatically controlled engine oil cooler. My Tahoe with the towing package includes a small engine oil cooler and a larger transmission cooler. I agree that transmission oil cooling is more important than engine oil cooling. I also think that routing the transmission oil thru the radiator is a mistake when there is a separate external transmission oil cooler and the oil flow is thermostatically controlled by the transmission.

I had not planned to monitor my oil temperatures because I don't plan to tow more than a small utility trailer with my Sport. I'm adding all of the coolers because I want the engine and transmission to last as long as possible after they are rebuilt sometime in the next two years. When I finally complete the oil management system (no leaks, no problems) I will switch to all synthetic oils and determine the performance and gas mileage improvement. What is the cheapest and easiest method to temporarily monitor oil temps? Does the transmission report its oil temperature to the PCM? If so, I might me able to log it if I bought an SCT SF3.

Progress on the oil management system has been slow this week because I had minor surgery (skin cancer spot on my temple) and I'm not supposed to perspire much since the stitches are water soluble. I keep a fan blowing on my face when working on my Sport.

Below is a photo of the second transmission oil cooler installed on the driver side before cutting off the cable ties.

I was surprised at how rigidly the coolers are mounted with the combination of aluminum brackets and plastic ties.
Below is a photo showing both transmission coolers awaiting oil lines.

The arrows in the photo below indicate the intended location of the engine oil cooler.

The engine oil cooler will fill most of the opening.
The photo below shows my first attempt at fabricating mounting brackets for the engine oil cooler.

I still have to drill holes in the brackets before I can try them out.

There's a 3 quart Accusump listed on eBay that I'm tempted to bid on but I don't know where I can find room on my Sport to install it.

[CDW6212R]

The SOHC has the oil filter in the right rear, so I'd place the accumulator on the frame rail outside if that area. Al located his bypass filter etc there on his 99 SOHC truck.

If you add external lines and filters, then the easiest way to get temperatures is at the adapters. I'm going to place a temperature sensor in my trans pan of my V8 truck, I think that's the hottest location.

[2000StreetRod]

Originally Posted by CDW6212R

The SOHC has the oil filter in the right rear, so I'd place the accumulator on the frame rail outside if that area. Al located his bypass filter etc there on his 99 SOHC truck.

If you add external lines and filters, then the easiest way to get temperatures is at the adapters. I'm going to place a temperature sensor in my trans pan of my V8 truck, I think that's the hottest location.

Al Franklin eventually moved his dual filter assembly to the same location mine will be. I think he wanted direct air flow on his clamp on filter fins and to improve accessibility. I want to reserve the frame rail area near the exhaust for a future exhaust modification but that's probably the best location for an accumulator.

I agree that the best location for a transmission oil temp sending unit is in the pan where it can read the highest temperature. I should change my in the pan filter when I convert to synthetic oil. Maybe I'll wait until it's rebuilt and add a drain plug at that time. The only reason I might need a sensor is to detect the failure of the internal 5R55E thermostatic control. I recall that you suspected yours might be opening the external path at too high a temp. Warming synthetic oil may not be as important as warming standard oil so I may have the mod done to prevent internal circulation.

Does anyone know if the 5R55E reads the temp of the oil and reports it to the PCM? I'd ask James Henson but I suspect he is very busy getting things in order after his wreck.

[CDW6212R]

I have seen/read of a temp sensor mentioned, but from what I've learned before the PCM doesn't have that information. I think it's not on these model Fords, but maybe the 2002+ next generation PCM's.

I'm very interested to see what temps you achieve with the two coolers without the radiator. The coolers I will have on my V8 will be about the same, and I'm wondering if the radiator cooler is of no use then. The radiator cooler transfers heat better, but if it's heating more than it's cooling, why use it. That's great for Winter warm ups, but Summer heat is a bigger issue.

I wonder if one of the thermostatic adapters for oil can be used to heat ATF, diverting fluid away from the radiator after a certain temperature. I haven't looked into those things in 20 years or more.

[2000StreetRod]

Originally Posted by CDW6212R

. . . The coolers I will have on my V8 will be about the same, and I'm wondering if the radiator cooler is of no use then. The radiator cooler transfers heat better, but if it's heating more than it's cooling, why use it. That's great for Winter warm ups, but Summer heat is a bigger issue.

I wonder if one of the thermostatic adapters for oil can be used to heat ATF, diverting fluid away from the radiator after a certain temperature. I haven't looked into those things in 20 years or more.

For my 5R55E, in the stock cooler configuration, if the internal thermostatic control is working properly, the oil will not circulate thru the radiator unless it has already warmed up. That's why for me it is a wasted resource unless the oil temp exceeds the radiator temp and the radiator acts as a cooler.

I guess I could add a T at the input to my full flow trans oil filter and add a temp sending unit. The output of the coolers are hose barb and not conducive to adding a sending unit. I've started bidding on an AutoMeter electrical temp guage and sending unit with a range of 100 to 250 degrees F.

[2000StreetRod]

I received an answer to one of my questions about their bypass oil filter. It does not contain a bypass valve and they recommend that the oil return from the bypass filter be unpressurized. I guess the penalty in my application will be less flow thru the filter since my return will be pressurized. I did not receive an answer to my question about the need for a restrictor.

I also received an answer to one of my questions about their AMS oiler. My interpretation of the answer is that the oiler utilizes a piston in a cylinder with a spring (instead of air pressure like Accusump) on one side of the piston and pressurized engine oil on the other side controlled by a solenoid valve.

[CDW6212R]

Ditto, their pre-oiler pushes some amount like 7 ounces of oil in. I keep forgetting that, that was the second reason I decided against it.

[2000StreetRod]

Originally Posted by CDW6212R

Ditto, their pre-oiler pushes some amount like 7 ounces of oil in. I keep forgetting that, that was the second reason I decided against it.

I have also decided against the AMS Oiler. Eventually, oil from the pressure side will leak past the piston and collect on the spring side. The thinner the oil, the quicker it will leak past the piston. To my knowledge, there is no way to drain the collected oil. Also, eventually the solenoid valve will fail. I like the idea of a separate solenoid valve that can be replaced. Like you, I would like a larger capacity than 7 ounces. I'm currrently bidding on a used Accusump but I suspect the winning bid will be higher than I want to pay.