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Lately I've noticed and participated in several posts that have to do with running 700-R4 and 200-4R transmissions. I fail to understand why people take such a cavalier attitude about not installing a transmission temperature gauge. A couple years ago I read an article about the effects of heat on ATF. There is a correlation between heat and transmission longevity. Take a look at the chart and see for yourself.:eek:
 

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I'm not sure I buy those numbers. I don't think it's as bad as the chart says.

I must admit that I've never had a gauge on a street driven car until I got my 09 GMC. On it, no towing and not running in "tow mode", the temperature is all over the place. Anywhere from 150-200 degrees F, sometimes more but not often. That's after the engine is warmed, in "normal" driving. This does show though that it has a separate air to oil cooler after the cooler that's in the radiator tank. Which I used to think was unnecessary for a stock type installation, at least on a passenger vehicle. In other words, for a long time I thought that 200-225 degrees was Ok, and I'm not so sure it still isn't.
 

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As long as your temp gauge is accurate, and your cooling system is up to snuff, I don't see a need for a trans temp gauge. But then if you tow a heavy load, in all kinds of temps and altitudes, it might be a wise investment, along with a trans cooler. Another thing most people forget, is to change the trans fluid. It has additives that dissipate with miles.
 

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Rick, I have read three studies that confirm these findings. The last was a Study by The Nat'l Assoc of State Foresters with the F350 and F450 Trucks in their fleets. They were having transmission failures and went to the ATF manufacturers for answers. The NASF study indicated "the ATF manufacturers suggest that for every 20 degrees increase in operating temperature above 175 degrees F., the life of the fluid is cut in half.":eek:
Nearly nine out of ten transmission failures occur from overheating & fluid contamination according to the Automatic Transmission Rebuilders Association.
 

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Interesting post. Where is the correct place to put the gauge? In the line leaving the transmission going to the cooler? What kind of cooler is everyone using? All I have on mine is the one in the radiator, but I have thought about adding one.
 

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"the life of the fluid is cut in half"

Fluid, not transmission. Of course that could be the same.

I don't disagree with the general premise, I just think the numbers are overstated. The numbers are overstated by those who want to sell fluid, especially "good" fluid, those who want to sell coolers, and especially by those who want to limit their warranty exposure (can you say Bow Tie Overdrives?).
 

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"the life of the fluid is cut in half"

Fluid, not transmission. Of course that could be the same.

I don't disagree with the general premise, I just think the numbers are overstated. The numbers are overstated by those who want to sell fluid, especially "good" fluid, those who want to sell coolers, and especially by those who want to limit their warranty exposure (can you say Bow Tie Overdrives?).
Bow tie Overdrives doesn't give you a warranty. You must earn it by jumping through all their hoops. I believe in their warranty program. They install every transmission and run it and record the data. Then, after you install the transmission, you call in the pressure readings to see if it matches the one's the day BTO tested it. Make sense. Then you get the go ahead to go on a test drive and put the transmission through their tests and write down the data. Still makes good sense. Then, you call BTO with data for a warranty. I passed without hiccups. The 200-R4 runs flawlessly and I'm glad I chose BTO.
 

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Yes you get to "earn" the warranty twice. First with their exhorbitant prices, then you have to jump through their hoops. I don't care to do either, build my own.
 

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I push snow and pull a 24 ft enclosed trailer with a 87 GMC 1/2 with a 700. I run a high capacity B&M deep pan with an extended pickup and a large cooler. I am a firm believer in keeping them cool.
 

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I think the key here is Towing/Plowing. The more you tow, the more you need coolers and temp gauges. For a 400 HP car used to go get coffee, that doesn;t have a trailer hitch or a snow plow, Its probably overkill.
But overkill is often the norm around here. We boys and our toys.
 

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I have deep pans & coolers on Camaros that only run 1/8 to 1/4 at a time. However they have TH 400s with 4000-5000 rpm converters and 500-700 hp. My 56 has a deep pan on its 350 with a tubular cooler built in, I am building a 700 for my 56 guess what its getting.
 

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Well it's time to fess up here, and say that I've been fighting what I thought was an overheating problem on my 200-4r ever since I bought it (used). I have plumbed the cooling lines thru my PRC radiator, and then to a Hayden cooler with two 8" puller fans activated by a 180 degree thermal switch (on the return line...just before it comes back into the trans). For months now,when I take it for a long cruise on the freeway, it evenually starts to put fluid out the overflow. Run it long enough like that (15 or 20 minutes) and the fluid is so low it begins to shift funny.

So I FINALLY got around to welding in another bung into the pan, and put a trans temp guage in.

Yep...getting hot.

Within 15 minutes of cruizing the freeway on a level surface, it climbs to 190, 5 to 10 more minutes and it's starting to blow out fluid thru the overflow at 220 degrees.

Fans are working, but I'm not sure if the location I placed the hayden cooler is getting enough air. Seems like this trans shouldn't run this hot...

Here's a pic of the underside of the front cowl area where I placed the cooler/fans.



Im running a 350 SBC running max 300 hp, with an 1800-2000 stall converter, which I can feel "locks up" immedately after it goes into overdrive (as it should).

What makes a 200-4r run hot? Do I really have to splurge $250 for a deep pan in addition to all this cooling stuff I've done? I'm about ready to remove it and take it to the trans rebuild guy to tear down, but I'd like to know what makes them run hot. It sure doesnt' feel like it's slipping when driving, but when I've taken the pan off for various reasons, there's always a fine black residue in the bottom of the pan. clutches slipping that aren't easily detectable? Pump is putting out 150 pounds of pressure when in overdrive at 220 degrees at 70mph...so I dont' suspect the pump is the faulty component....

Confused in SoCal...
 

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Well it's time to fess up here, and say that I've been fighting what I thought was an overheating problem on my 200-4r ever since I bought it (used). I have plumbed the cooling lines thru my PRC radiator, and then to a Hayden cooler with two 8" puller fans activated by a 180 degree thermal switch (on the return line...just before it comes back into the trans). For months now,when I take it for a long cruise on the freeway, it evenually starts to put fluid out the overflow. Run it long enough like that (15 or 20 minutes) and the fluid is so low it begins to shift funny.

So I FINALLY got around to welding in another bung into the pan, and put a trans temp guage in.

Yep...getting hot.

Within 15 minutes of cruizing the freeway on a level surface, it climbs to 190, 5 to 10 more minutes and it's starting to blow out fluid thru the overflow at 220 degrees.

Fans are working, but I'm not sure if the location I placed the hayden cooler is getting enough air. Seems like this trans shouldn't run this hot...

Here's a pic of the underside of the front cowl area where I placed the cooler/fans.



Im running a 350 SBC running max 300 hp, with an 1800-2000 stall converter, which I can feel "locks up" immedately after it goes into overdrive (as it should).

What makes a 200-4r run hot? Do I really have to splurge $250 for a deep pan in addition to all this cooling stuff I've done? I'm about ready to remove it and take it to the trans rebuild guy to tear down, but I'd like to know what makes them run hot. It sure doesnt' feel like it's slipping when driving, but when I've taken the pan off for various reasons, there's always a fine black residue in the bottom of the pan. clutches slipping that aren't easily detectable? Pump is putting out 150 pounds of pressure when in overdrive at 220 degrees at 70mph...so I dont' suspect the pump is the faulty component....

Confused in SoCal...
The torque converter selonoid is bad. when they are bad it will cook the fluid. About a $30 fix. My son had the same problem with his 2004R in his turbo Buick.
 

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I'm not convinced the torque converter lockup solenoid isn't functioning, because I can feel it lock up (rpms drop) a few seconds after going into overdrive. When I put my foot into it a bit, it drops out of lockup (rpms go up a few hundred). A bit more foot into it, and it downshifts to 3rd just fine.

And it has a brand new torque converter and I changed out that solenoid for a new one when I had the trans pan out a month ago...
 

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I dont know where you are shopping for deep pans but I find them at swap meets or Ebay for 15-100 dollars dependind on chrome or alum. If you are going to buy one get one that has an extended pickup. No point in running one without it.
 

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Time for a quick update. I took the trans out and took it to a local rebuider "in complete frustration" over all the time and diligence I've put into getting this thing to run without getting hot.

He tore it down and found that the 2nd, 3rd, and 4th grear clutches were slipping...and that was generating so much heat, that the cooling system couldn't compensate.

So he did a complete rebuild with all new components, clutches, new super servo, hardened stator, 10vane pump, etc. and it now runs and shifts strong. The temp gauge shows it running no hotter than 190 (just under what the water temp gauge shows...now that I've plumbed the trans cooling lines thru the radiator BEFORE they go thru the hayden/fan cooler.

So...bottom line here...beware when buying a used automatic transmission...you really don't know what you're getting until you install it and run it and find out.

Not too terribly expenisve lesson here...but time consuming.

happy to have it running in time for Cruisin' for a Cure show in Costa Mesa this weekend.
 
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