To Cool Tranny or Not To Cool?

[Macgyver]

Ok a little mistake on my part I think here. After replacing the intake and everyhting and finally working on the timing and carb issue, the upper inlet hose on my radiator finally blew out. Being that it was a beautiful piece of plastic I figured that I would just replace it seeming how there was another leak somewhere down low. Also to aid in the longevity of the engine I figured a full relpacement of the entire cooling system would be a good idea.

I grabbed an aluminum one from summit and it arrived this week. I didint even bother to look, or it never occured to me, that the transmission fluid was running throuhg the radiator. The new one doesnt have the 2 small provisions for it on the passenger side.

So my questoin is, is that a bad thing that Im no longer cooling the transmission fluid? Should I just wait and order another one? As soon as I sell my jeep in a month or 2 I plan to swap out the th350 for a 700r. Any advice guys adn girls?

How hard would it be to add one on later since I already have the lines running. Also how would i stop up the lines if I do go w/o it?
I cant stand it any longer though, I havent drivin her in two months and I really want to break in the Holley and Performer Intake!!!

 

[Robin7TFour]

Mac, don't run the car without the cooler. you'll burn up the fluid and may do some damage to the bands inside. any good auto parts store will have add-on coolers that comes with zip ties to connect it to the radiator. or you could fabricate brackets to allow the cooler to lay flat just above the front valance. if you do lay it flat make sure it's close to the area of the front spoiler,which will help with air being pushed up from the spoiler.


good luck

robin

 

[mike weyman]

almost any tempo in the junkyard will have a cooler, i bought one for 5 dollars,aftermarket start at about 50 dollars.

 

[Robin7TFour]

Mike, very good idea. however, with all the urban sprawl here in Orlando all of the good salvage yards are disappearing...so many times it's just more necessary to buy new

Robin

 

[Macgyver]

Damn, good thing I asked! I guess its time to go to Pick n Pull. Sweet, I love that place. Does anyone have any pics of one or something to go on?

Mike, wheres it going to be located on a tempo? Do they add them to most Auto tranny cars after maybe 85 and up? Are they located on the front passenger side?

 

[Robin7TFour]

Mac ,go to Summit or Jeg's on line catalog. you can see what an add-on cooler looks like..

yes i love this site too

Robin

 

[drags1998]

Dont run it without a cooler, I would buy a NEW cooler, or if you get a used one make sure you clean it out really good!!! Most new coolers come with mounting straps& or Zip ties!! Just my .02 worth

 

[mike weyman]

behind the grill in front of the radiator,looks like a little radiator,just run the two lines to it.

 

[Pancho]

Just my $0.02, but....

I'd return the radiator and get one for an automatic with the cooler built in, THEN add an external, run in series. The oil-to-water coolers internal to the radiator are much more efficient than oil-to-air ones you hang on the outside; and if you are contemplating a 700R4 conversion you'll need all the cooling you can get.

//Pancho

 

[Evolution1980]

Ok a little mistake on my part I think here. I grabbed an aluminum one from summit and it arrived this week. I didint even bother to look, or it never occured to me, that the transmission fluid was running throuhg the radiator. The new one doesnt have the 2 small provisions for it on the passenger side.

So my questoin is, is that a bad thing that Im no longer cooling the transmission fluid? Should I just wait and order another one? As soon as I sell my jeep in a month or 2 I plan to swap out the th350 for a 700r. Any advice guys adn girls?

How hard would it be to add one on later since I already have the lines running. Also how would i stop up the lines if I do go w/o it?
I cant stand it any longer though, I havent drivin her in two months and I really want to break in the Holley and Performer Intake!!!

Running your transmission without cooling will destroy it. Period.

The radiator has the inlets for the transmission, but it's not to cool the trans fluid. It's to heat it up and bring it up to normal operating temperature, which is about 150°F.

From there, a separate cooler may be needed, but only if your trans is getting too hot. If you do get the 700R4 in the future (mine arrived last night!), you will need to do all this anyways. If you buy the trans from Bowtie Overdrives like I did (and HIGHLY recommend), you will need to be exceptionally specific about how everything is setup in order to utilize their warranty.
If your trans isn't running within the proper operating temperature (either too hot or too cool), you will damage the components, and you may not know it until it's too late.

 

[vettenick]

If you decide on an auxiliary cooler, make sure that it will fit. It's real tight, especially when you open the hood.

 

[Vanity Plate Bob]

If a cooler can be a heater why cant a heater be a cooler. Oh that's alright. I understand.

Remember. If the factory put ''it'' on, whatever ''it'' is it most likely is necessary.

 

[Macgyver]

Well I have anther mini radiator in front of it already that the AC runs to. Cant I disconnect those lines and run it to the Tranny. Im not going to run the AC anymore anyways.

How will that go, do I just run the lines to the AC cooler and it will do its own thing or do I need a pump of some sort. Im really tired of spending money this week.

 

[Pancho]

Uhhhh, let me think about that..... No.

The 'mini radiator' is an A/C condenser; I've never had one apart but I would imagine the passages are way too small to work as a transmission cooler.

This is not an area to cut corners, especially if you're thinking of dropping in a 700R4.

The transmissions have their own pump for the fluid coolers, so you need to make sure they (the coolers) have low restriction otherwise you'll starve the transmission of fluid.

//Pancho

 

[Vettehead Mikey]

Well I have anther mini radiator in front of it already that the AC runs to. Cant I disconnect those lines and run it to the Tranny. Im not going to run the AC anymore anyways.

How will that go, do I just run the lines to the AC cooler and it will do its own thing or do I need a pump of some sort. Im really tired of spending money this week.

And just think, the next owner of this car will moan and groan on some internet site about 'Bubba' having worked on his new car. Do you really want to do these drastic short cuts?

Why not just get the correct radiator and be done with it?

 

[WayneLBurnham]

Yes, you can. No, you shouldn't.

How will that go, do I just run the lines to the AC cooler and it will do its own thing or do I need a pump of some sort. Im really tired of spending money this week.

The tranny has it's own fluid pump to send fluid to the converter and this is what moves the fluid through the radiator. No additional pump is needed, like in the rare differential coolers you find on some vettes (some of these also flow without a pump, just from the differential pressure from the cooling of the fluid - but that always seemed "iffy" to me, especially with something as viscous as differential fluid.)

BTW, I am still crying from the evil "bubba" remarks...hehehehe.....

You CAN do this (use an A/C "condensor",) in fact this is where most old style "bubba" auxilliary oil and tranny coolers came from - either automotive or window unit A/C "condensers".

Ready made/bolt on kit coolers from the 287 people who make them weren't extant as recently as the early 80's - and those that were around were pricey.

There's the rub though - they have some NIFTY and SMALL ones that are quite reasonable now - but ALL of these are really rated at being AUXILLIARY coolers. They usually run the plumbing from the standard on-the-coolant-radiator one to the auxilliary one and back to the tranny. This will cool the tranny way below the percentage of the engine coolant temp, which it picks up some of - sort of "polishing" the cooling process, down to a nice <35-50 degrees over ambient maximum.

Absolutely send the radiator back and get the right one. I know it's a pain.

THEN as several posters also recommended, you should definitely get the highest GVW/temp reduction auxilliary cooler you can fit, without getting silly on costs.

You should be thinking an auxilliary oil cooler too with Texas heat. Even running Mobil 1/Royal Purple/Red Line/Castrol/whoever's full synthetic, breakdown and working viscosity are very negatively affected by even modest increases in oil temp above 220 or so.

Back to the tranny though, I have a Turbo 400 which is hopefully a refund check away from getting a Gear Vendors Overdrive added. It has a mild stall converter - an 11" about 1875RPM. I just recently had it (and the converter)rebuilt (reverse died, badly ), a nice sharp shift kit installed, having an electronic speedo sender put in for my new Nordskog panel AND having a tranny temp sensor drilled and tapped into the case from above for the auxilliary gauge panel I already had on the extremely "bubba'ed" heap.

I just made a "rescue run" for some silly relative who missed the bus back from Bossier city (from Dallas) yesterday. Holding a steady 90-95 for the 210 mile one way trip, with an engine RPM of 4200-4500 (I have 3.73's in a Tom's Differential 12 bolt), with an air temp peaking at 75, the tranny temp made it up to 182, and was usually over 175.

That's too high. Not a lot, but some. 160 - even 150 with such a low air temperature would be more ideal. When we get to 105 in a week or two for the next six months, it's probably going to see 210+. I'm gald I use Royal Purple full synthetic, but that won't save those bands forever (even though they did make it for a hard 45,000 miles in the 18 months I've been abusing the poor thing.)

Now my mild stall converter will raise the temp a LITTLE, but the neck braking shift kit will also lower it. (The former increases higher rev slipping a little in exchange for harsher take off, and the latter eliminates a lot of heat-inducing slip and ALSO happens to yield a much better painful shift!) So it's pretty much a wash there compared to a stock tranny. The higher RPM operation in front of the pumpkin makes the tranny pump run faster than normal, thus increases cooling (within the limits of the heat transfer capacity of the cooling appurtenance - which for a very short while is just the plain "in-radiator" one.)

A non-lockup converter overdrive generates an ENORMOUS amount more heat and turns slower (at the fluid pump) to make the problem worse. While not in consideration here in either case, I BELIEVE a lock up converter is much better for this, but am not sure. The converter is where something like 65-75% of the heat in a tranny is generated though, as I recall. (Notice manual trannies and differentials rarely have coolers - generally only at high speed or power levels.)

Good Luck and good luck on the tranny swap!

 

[Macgyver]

All right all right Ill buy one.


Seriously thoguh thank you for all the info guys I really appreciate it.

 

[Vanity Plate Bob]

As my daughter said today "why keep the encyclopedias when we have a PC and CAC. All that info and no sales person.
Speaking of years of junk (collectibless) in the attic.

Does CAC have spellcheck? (Look it up in the cyclone-pidia.)

 

[Robin7TFour]

wayne what camshaft are you using in your motor? you answered alot of questions i had.

robin

 

[WayneLBurnham]

Bone stock replacement motor

I haven't touched the mill yet. I've spent...wow, I can ALMOST admit it easily....right at about $45K on this heap to build a platform for a monster motor and haven't.....even.....touched......the..... motor......it .....came....with.....wow (what an IDIOT!)

The current little thing in there is a cheapy "target" motor variety of a Goodwrench crate. (265hp/310 torque, IIRC) The only good things on it are the powdered rods and four bolt. No forged crank, pistons or, for that matter, rods. It has a number of bolt ons, but nothing deeper than intake.

I think the cam is all of a GOOD third inch lift, except for the ones that are flattened... Actually that tiny lift and those small valves (not to mention the too often hit rev 6250 set rev limiter!) are probably EXACTLY what has allowed it to live so, so long at such reasonably high RPM without so much as new valve springs or a chain.... The momentum from a decent lift or heavier larger valves would have had to crater by now... I have to say, for a very few grocery getter cheap mill, that $1300 TT&L "Target Motor" is as durable as an old 318 mopar...still wish the previous owners of this lemon had gone ahead and doubled that and put in the next one up from the General's bake sale.

I decided since I cannot possibly get to "The Engine of Truth" for several years I need a short term build up of this small block. I'm doing a shake and bake kit with the Edelbrock Performer RPM Air Gap package, which is I believe .488/.510 - 234/244 deg at 0.050"+, on 112 centers. I bought the heads and covers and some other small things, but not the cam, intake, roller rockers, push rods, TC, etc. yet.

I WAS going to go with a newly built all forged stroker short block and the new roller version of Edlebrock's set up (I worry those powdered rods, as light and strong and especially UNIFORM that they are, and especially that cast crank are really a good thing to use in something developing 410/435 hp/tq as Edelbrock swears on a stack of assorted holy books their set up produces.) But my local place will give me the balanced parts or assembled for a really decent 7700RPM useful and 8200 RPM max redline all forged stroker short block for $2200/$3100 and the difference in the roller cam set up approaches $700. For that other $3-3.75K and only much greater useful RPM range (way past the 6500 the Performer RPM setup is designed for) I only get an increase of 70-85 hp and 60-70 tq. (15-20%/12-15%) over the cheap build up.

That total price is in the range of a medium crate bigblock and way, way more than I want to spend on an interrim engine, so I am going to go with the cheaper upgrade and no bottom end. If it blows, THEN I'll spend the rest I don't have on the full deal!

Before even that modest build up though, I WANT MY OVERDRIVE! I also think I need to address some cooling issues now. (Looks like ANOTHER summer without an A/C...what joy!)