Welcome to the next contribution to the
The Official Pirate4x4.com Jeep Talk Bible (http://www.pirate4x4.com/forum/showthread.php?t=705122)

Topic of the Month Oil Cooling

Show pics and discuss modifications you have done to upgrade your Oil cooling system. Topics include: Transmission coolers, Power steering coolers, Engine Oil coolers, plate Coolers vs tube style coolers, Fans, and mounting locations.

Also see:
Engine Oiling (http://www.pirate4x4.com/tech/billavista/Oiling/#cooler)
GriffinThermalProductsKingoftheHammersRadReview (http://www.pirate4x4.com/tech/billavista/Cooling/#GriffinThermalProductsKingoftheHammersRadReview)
The Pirate Cooling Bible (http://www.pirate4x4.com/tech/billavista/Cooling/)

Since I ditched my AC after going windowless I used the factory AC condenser from my 88XJ as the Trans cooler. It is mounted in the factory location in front of my Radiator. Im running an Th400 trans so that wont be common with what your running but I have a deep aluminum finned pan, it adds oil capacity and helps keep it cool.

For Ram assist and full hydro I use a tube (not plate) style trans cooler for the power steering pump return. The plate style coolers are efficient but for steering they will foam up your PS fluid. I run PS fluid not ATF when I can because its better for the seals.

I would like to add oil gauges for the trans, steering and engine oil.
I would like to add a dual circuit tube cooler for the trans and engine oil and relocated it away from the radiator with a dedicated fan. The winch, AC condenser and PS cooler do restrict the flow for my radiator.

My AW4 was overheating. The reason was a bad torgue converter lockup solenoid. I dropped the pan and replaced it. I also built/installed a deeper pan.
http://i149.photobucket.com/albums/s74/4x4hiker/Picture208.jpg
I lowerd the filter pick up 1 1/2 inches as the pan was 1 1/2 inches deeper.
I tacked on some sheet metal:
http://i149.photobucket.com/albums/s74/4x4hiker/Picture205.jpg
And sealed it up with hi-temp RTV:
http://i149.photobucket.com/albums/s74/4x4hiker/Picture206.jpg
http://i149.photobucket.com/albums/s74/4x4hiker/Picture207.jpg

Though not proven yet becuase I havn't moved the rig out of the shop since this project started. I have done several things

Power steering finned tube cooler to increase fluid volume and surface area.

Dual remote oil filters increase volume as well as increasing surface area.

Moroso accumulater to increase oil volume.

So far I have added 3.5 quarts of oil to the system with these mods.

A related thread in General:How much Tranny cooler is enough for KOH??
http://www.pirate4x4.com/forum/showthread.php?t=914597

OK, I've got a some info to add to this topic.

I originally ran a derale cooler with an electric fan on the Jeepspeed, but it did not even come close to cooling the AW4 trans under race conditions. I had it mounted in one of the rear window as shown in the picture. I also made a scoop and ran it with and without the scoop- either way it would pin at 250 during a race unless I backed off the throttle.

After the temp issues, I made a few changes. I went with a huge Fluidyne cooler with electric fan, moved the cooler to behind the front seats hoping to get more air flow, & built a heat shield for the cooler lines.

Now it runs too cool if I leave the fan on. I'm thinking of adding an inline thermostat since the AW4 does not like to run when it is cold and will do some weird stuff at 130 degrees.

Do you think it was mostly the added heat shield that helped?

Do you think it was mostly the added heat shield that helped?

I certainly think it helped, but the Fluidyne cooler is about twice the size as the derale unit it replaced. The large cooler probably made the biggest difference. Unfortunately, I did all the upgrades at once. The heat shield is also a good safety factor and should help prevent premature failure of the braided lines due to excessive heat exposure.

What temperature range should power steering fluid be under ideal operating conditions?

Some hummers run transfer case coolers. They should swap into a 231.

Part No. 6011652
NSN: 2520-01-358-7698

Does anyone run engine oil coolers? I'm entertaining the idea if I switch to a remote oil filter. Is it a good idea, or not necesary for a 1988 4.0?

Below is Appendix 8-1 of the Chevrolet Motor Home Chassis Service Guide. It has an excellent 3 page treatment of the subject including cooler comments. Some quotes:

"OIL TEMPERATURE MEASURED AT CONVERTER OUTLET TO COOLER 300F is the maximum temperature. This is the normal place to install a temperature gage or signal. The temperature in this location will vary significantly with each vehicle start-up or hill. If the temperature reaches 350F, reduce throttle. To lower the transmission temperature with the transmission in NEUTRAL, run the engine at 1,200 RPM for 2-3 minutes to cool the oil. Do
not allow the converter outlet temperature to exceed 350F. Keep a close check to prevent the engine cooling system from overheating. 350F would be typical of rocking the vehicle in mud, snow, or sand, or a transmission in stall (full throttle, no vehicle movement). When the transmission is in stall, the transmission will develop heat at a rate of one degree per second
of stall.
"OIL TEMPERATURES MEASURED IN THE SUMP OR OIL PAN
150F -- Minimum operating temperature for continuous operation. It is possible in low ambient temperature to overcool the transmission with oil to air-type coolers; it is hard to overcool if used in conjunction with oil to water coolers installed in most standard automotive radiators.
190F-200F -- Maximum oil level checking temperature. Beyond this, readings are not reliable because of expansion.
285F -- Maximum sump/oil pan temperatures for short duration such as a long hill climb.
300F -- Metal parts inside the transmission begin to warp and distort in varying degrees, seals melt rapidly, and transmission fluid life is extremely short due to oxidation and distress.

"AUTOMATIC TRANSMISSION FLUID OXIDATION Automatic transmission fluid
can provide up to 100,000 miles of service before oxidation occurs under normal operating temperatures of about 170F. Above normal operating temperatures, the oxidation rate doubles (useful life of the fluid is cut in half) with each 20 degree increase in temperature. The approximate life expectancy at various temperatures is a follows:
Degrees F Miles
175 100,000
195 50,000
212 25,000
235 12,000
255 6,000
275 3,000
295 1,500
315 750
335 325
375 80
390 40
415 Less than 30 minutes
NOTE: THE ABOVE CHART IS BASED ON THE ASSUMPTION THAT OIL TEMPERATURE REMAINS CONSTANT FOR THE MILES INDICATED. TEMPERATURES WHICH APPEAR FOR SHORT PERIODS, SUCH AS CLIMBING HILLS, ETC., WOULD NEED TO BE AVERAGED AGAINST NORMAL OPERATING TEMPERATURES TO DETERMINE ACTUAL LIFE EXPECTANCY."

They caution against using Type F vs Dexron IIE because Type F is a higher friction fluid, yielding higher shock loads and harsher shifts.

Also state that odor and color change ARE NOT satisfactory criteria for recommending fluid drain and refill because "With the Dexron II fluid, rapid
loss of the red color and darkening of the new fluids are normal and DO NOT
affect their performance. Contrary to past performance, the service
technical SHOULD NOT CONSIDER A DARK APPEARANCE OR BURNT ODOR as the signal to change fluid. ... Short of a laboratory analysis the owner's manual drain recommendation should be followed."

Their position is somewhat neutral on after market coolers, basing the decision on initial cost, need, potential extra leak points, line fatique/failure, and installation quality. To judge need (in the absence of a gage) estimating temperature rise from dipstick readings.

"NOTE: After-market transmission temperature gage should be installed in the lower (hot) oil line as viewed from entering the radiator. "After-market external oil to air cooler should be installed after the GM transmission cooler. The lower (hot) line should go first into the lower
fitting of the GM radiator cooler then out from the top fitting to the after-market oil to air cooler.
"Extreme cold weather may require the after-market oil to air cooler to be covered so not to cool the oil to (sic) much.
"After-market external filter should be installed in the lower (hot) oil line to prevent any debris from reaching the radiator cooler if the filter is being installed in conjunction with a transmission failure or overhaul."

http://www.pirate4x4.com/forum/showthread.php?t=455487&highlight=th400+cooling&page=2


350F would be typical of rocking the vehicle in mud, snow, or sand, or a transmission in stall (full throttle, no vehicle movement). When the transmission is in stall, the transmission will develop heat at a rate of one degree per second
of stall.
Knowing Gpm that passes the cooler then it should be possible to calculate heat produced.

FSJ Cherokee SBC 350 engine oil cooler 10 x 8 inches 12 inch fan. Air intake from wheel well 3 x 2 inch holes covered by down facing scoop. I run my engine cold, average 70C, the engine oil stays below 60C.

http://i236.photobucket.com/albums/ff267/SubicJeep/Fans/Chevy-oilcooler10079.jpg

http://i236.photobucket.com/albums/ff267/SubicJeep/1-Cherokee%202010/oilcooler.jpg

Engine oil you want to keep around 200-220F so that any moisture in the oil will evaporate.

Power steering fluid is similar to ATF but can handle higher operating temps and is formulated different for rubber seals and hoses. It is also more liquid at lower temps down to -20F.

Power steering operating temps 150-300F 250F typical max operating temp.

There are special oils, synthetics and such that can withstand higher temps but above 300F and your hoses and seals will be the weak linnk.

Engine oil you want to keep around 200-220F so that any moisture in the oil will evaporate. .

To keep a very high engine oil temperature just because of potentially moisture... hmmm just change oil more often and water evaporates at lower temperatures also.

My philosophy is, by starting at a lower operational temperature will give you more margin before everything starts to "boil" .
Change oil more often if moisture is a problem.

I am running a SBC 350 as per cast numbers its 1969 - 1979, I am not worried...... a high performance smog motor may need an other approach.

But we have not defined how long we have to maintain these high temperatures, 10 minutes or 4 hours there is a big diff in cost between these times running in peak power.

There are posts here in Pirate about uncomfortable high temperatures (for driver) in buggies so maybe starting at lower temperature is a solution, I am referring to water and oil temperatures. This is a package deal when it comes to cooling.

Power steering fluid is similar to ATF but can handle higher operating temps and is formulated different for rubber seals and hoses. It is also more liquid at lower temps down to -20F.

Power steering operating temps 150-300F 250F typical max operating temp.

There are special oils, synthetics and such that can withstand higher temps but above 300F and your hoses and seals will be the weak linnk.

So in theory I could use the transmission cooler built into my radiator as a PS cooler, I was originally planning that until somebody mention that then my PS fluid would probably remain around 210. Now that that's not a problem it's time for a project. I could also have it run through a separate cooler after passing through the radiator, and mount the second cooler in front of the radiator so it cools the fluid more after the radiator pass.

To keep a very high engine oil temperature just because of potentially moisture... hmmm just change oil more often and water evaporates at lower temperatures also.

My philosophy is, by starting at a lower operational temperature will give you more margin before everything starts to "boil" .
Change oil more often if moisture is a problem.

I am running a SBC 350 as per cast numbers its 1969 - 1979, I am not worried...... a high performance smog motor may need an other approach.

But we have not defined how long we have to maintain these high temperatures, 10 minutes or 4 hours there is a big diff in cost between these times running in peak power.

There are posts here in Pirate about uncomfortable high temperatures (for driver) in buggies so maybe starting at lower temperature is a solution, I am referring to water and oil temperatures. This is a package deal when it comes to cooling.

You have the B&M super cool kit? thats what Im looking at doing with a 10in fan on it. Im thinking of running it with no thermostat on the fan, the keep it as cool as I can approach. Dont get much moisture in arizona anyways.

I added the B&M engine oil cooler to the 350 power FJ40 on the weekend.
On hot days It has marginal cooling for sustained speed. The added oil cooler didnt help at all. I wouldent recommend adding an oil cooler to lower your operating temps, keep your focus on the radiator.

http://wheelingarizona.com/forums/download/file.php?id=10975&t=1
http://wheelingarizona.com/forums/download/file.php?id=10976&t=1

Im allowed to post pics of a Toyota. :flipoff2:

This was a quick fix I did a few years back when the plastic keeper quick connect thing broke on a aw4 cooler line. The quick connects use metric threads, a few o rings, are prone to leakage, and pretty gay IMO. Now that I am reworking my exhaust for control arm clearance, I did the other fitting. The modification provides a little more clearance.

I used a 3/8npt hose barb and a 3/8 pipe tap. The tap calls for a 37/64 drill, I used a 9/16, works OK. Do not drill it out to deep.
http://i149.photobucket.com/albums/s74/4x4hiker/Picture258.jpg

I drilled it out to 9/16 and trimmed some off the top
http://i149.photobucket.com/albums/s74/4x4hiker/Picture259.jpg

and tapped
http://i149.photobucket.com/albums/s74/4x4hiker/Picture260.jpg

the pipe dope is not needed, I used it anyway
http://i149.photobucket.com/albums/s74/4x4hiker/Picture262.jpg

this picture shows the extra clearance I'll gain. The fitting on the left is already modified, the right is stock
http://i149.photobucket.com/albums/s74/4x4hiker/Picture263.jpg

I'm not a fan of using hoses unless needed and I don't think it's needed here. I don't think you gained all that much clearance either, as you can't bend the hose very tight to avoid kinking.

I changed the fitting off the AW4 to a 90* and ran the lines close to the tranny and wrapped them.

It made quite a bit more clearance for my upper link and exhaust there.

Hey, As I said when I joined I would pass on any helpfull info I picked up.
Well here`s a big one, As per Jeep Magazine The specified Operating temp of the XJ AW4 trans is between 125 and 176 degrees.

Without an Auxillary Trans fan cooler they found thier jeep running at 160 degrees up to 260 degrees!!! as stated heat is the killer of auto trannys.
At about 240 Degrees important additives cook off so add weight, Lift kits, bigger than stock wheels + skid plates that block air flow and think how it was designed for stock driving :flipoff:
Helps to use low range when wheeling. IMPORTANT( do not block rad air flow with trans cooler find another spot)

I think Jeep Magazine is invaluable.

Check out this site if you want cheeper prices on JP Mag.
http://ca.zinio.com/?cmpgn_var=MAG_Brand&rf=brandesv

May 2010 is the issue I found this info in and will tell you 10 things wrong with your XJ, YJ, CJ, TJ & JK

found this online and has more indepth info than I have knowledge of so check this out and make sure you at least skroll down to the bottom http://4x4trailhunters.com/tech/read/21

B&M #130-70274 Transmission Cooler 29,200 BTU
11'' x 11'' x 1-1/2''

http://www.jegs.com/images/photos/100/130/130-70274.jpg

http://i236.photobucket.com/albums/ff267/SubicJeep/1-Cherokee-2011/AT-Oilcooler.jpg

Running on road... 248F out from transmission. The fan, Ford one from two unit fan setup covers most of cooler area i.e. optimal. Pushes a lot of heat still dont know what the pan temperature is, but installed a temp sensor in pan also so next road trip we know how much the cooler is reducing the temperature.

The cooler is in the rear sucking air from under cargo area. (FSJ Cherokee)

Answer to previous thread about engine cooler.

The engine cooler is GM original from unknown car about same size to BM 70274. The engine oil temp in pan max 70 C in normal circumstances this does not push a lot of heat but the hotter the engine gets the more it cools, is it worth the money hmm maybe not. (Not an answer to over heating issues)

(FSJ)

http://naxja.org/forum/showthread.php?t=1045807&highlight=tranny+lines


Way to remove those blasted clips that are on the AW4.

http://naxja.org/forum/showthread.php?t=1045807&highlight=tranny+lines


Way to remove those blasted clips that are on the AW4.

Can't get the link to work...