I took the Hot Rod (1932 Ford 5W Coupe) for it's first "substantial" Shakedown Run today since building the car. I drove 100 miles roundtrip, on two lane, hilly/winding roads, at speeds that averaged 40-60mph. (previously, I had put about 20 miles on the car around town) Oil pressure was good and water temp never got above 185 degrees, usually about 175-180. The motor is a SBC 350 crate with (4) 2bbl Rochesters, tranny is a Gearstar 700R4, and rear end is a 9-inch with 3:70 gears. Outdoor ambient temperature was 88 degrees. My question is this: When I returned home, I got under the car to look & feel around. The transmission pan (deep finned aluminum) was too hot to touch and the rear end housing was hot enough that you couldn't keep your hand on the housing for any length of time (maybe a few seconds) For the first run/breakin run of the car, are these hot surface temperatures to be expexted? Should they cool down as things break in?
Trans temp around 200 degrees is ok, over 250 could be a problem. That's too hot to touch without getting burned. Rearend should probably be too hot to hold onto also. As long as there's oil in them, should be ok. And hopefully you have a good transmission cooler, and the lockup converter is functioning properly.
TrippleG, with the Gearstar tranny's they usually supple a higher stall converter, do you have one? Believe me because I work very closely with the shop that builds our tranny's and converters, they get the fluid HOT. The deep finned aluminum trans pan is just doing its job, partialy cooling/dissapating the heat. It's working almost like a heat sink. Are you running any additional trans cooler or just plumbed into the radiator. I run a 10" 3500 stall converter in my 26. The engines stays around 180-185, trans up to around 195-200, but try an touch the finned aluminum heat sink type cooler, and you'll be sorry!!. Rediculous HOT!! I run both the rad cooler and the heat sink type. Out of the trans first is the heat sink, and then into the bottom of the radiator, and back into the trans. Works excellent in the blazing heat of south Florida, TR
Also, if the ring and pinion are new, the manufacturer often recommends a " break-in " procedure. Most dont follow it, and some regret it. I highly recommend it, that's just me. And probably the company who made the gears too. From everything you mentioned in the original posting, nothing seems out of the ordinary. Hope that helps friend, TR
I don't know why they call it a trany cooler but I never run my trans lines through the radiator. That short 12" line is designed to heat the trans fluid for sub zero weather in winter like North Dakota. I usually run the lines to a cooler mounter under the frame to the rear area. You can even hook up a fan to help circulate air through it as well.
It keeps the trans fluid at operating temperature under normal/ mundane circumstances. Towing, performance converter, hopped up motor needs an auxiliary cooler. If you want to test the EOM trans cooling capabilities of the radiator, or think it doesn't cool the fluid; disconnect the lines from the radiator and loop them together. Drive it & Report the results. Ill wager those results will involve a tow truck and a rebuild.
I don't know. I have put over 200,000 miles on my coupe with an auto trans with no problems but it does have a non radiator cooler.
I agree with not running the rsdiator cooler if you have a big enough cooler installed in it's place. Also, with a high stall converter you get more heat, and I like a trans temp gauge to monitor the temp under that added stress. A good synthetic trans fluid will withstand the heat better than convetional also. Dave
Depends on the year of the 700-R4. My understanding is that the 1982 - 84 will overheat if the converter is not locked up in OD on a long run, while it's OK to not lock up the '85-up models.... 'Course on a long highway run it would be better to lock up any year for better efficiency and mileage....
My Gearstar 700R4 (Level 2), has a 1800-2000 stall converter. I've got it plumbed through the tranny cooler in the Walker Radiator I'm running (Gearstar Tech said he'd "accept" that), and I'm using Castrol DEX/MERC Automatic Transmission Fluid. Not being familiar with how hot this stuff is suppose to run, I thought I'd ask all you experts, before I ended up burning things up. Thanks for all the help and info.
Tripp, did Gearstar recommend the DEX/MERC? We use the CASTROL DEX VI, which is Semi-Synthetic, so you get the benefits of both synthetic and petroleum. The VI is backwards compatable with DEXII and DEX III too. If they want to to use it, by all means do. The DEX VI is holding up well for us, trans is full manual auto, all Kevlar frictions inside. The 10" converter makes for a LOT of heat too. A auxiliarly cooler is just good insurance, even though they " accept " what your running now. TR
I've always wondered why more guys don't install a trans temp gauge in their cars. We monitor everything else, but remain in the dark about what the tranny's doing. I have one in my motorhome, and it's really a relief to be able to monitor that th400. I have the lines go through the rad cooler, then the biggest aux cooler I could fit in there. Temp rarely goes above 175, and trans will snap your neck when it shifts. Heat is a transmissions worst enemy, they can't run too cool.
It's usually not a problem in a car, but you can cook a trans pretty quick in something heavy like a motorhome.
Actually, MOST transmission folks say that the transmission fluid temperature should be around 180 degrees. It works better, lubricates better and @ 180 ... moisture is not a problem. I always run mine thru a extra filter ( added capacity ) and then to a extra cooler. Then on to the cooler in the bottom of the radiator. The extra filter keeps wear and trash out of the system ( even before the pan filter ). The extra cooler cools the transmission fluid down ... and the radiator puts the correct amout of heat back into the fluid while also taking heat out of the radiator. WIN - WIN in my opinion. I have higher than stock stall speed in both my 32's ... and the transmission fluid gauge shows about 175/185 on both.
Duece, I like how you have the filter first, then the aux cooler, and then into the rad. This is how our tranny guys recommend it and they build some of the strongest auto transmissions in the world. ALL fluids are designed and engineered to work and perform at a certain temperature and within a certain range of temps. You wouldn't dyno a engine without adequate oil temp, nor would you/should you hammer a auto trans without sufficient oil temp. TR
Thanks My transmission converter guy suggested I do this ... about 25 years ago when I built the 32 roadster. The 32 Roadster has a Turbo 400 with the switch/pitch converter from a BUICK. The smaller converter in higher stall operation does generate more heat. I have over 50 thousand miles ( some of them HARD MILES ) without a single transmission issue. I guess he knew what he was talking about.
Excellent Duece, the only thing i was concerned with was the hard line from the tranny to the filter. I was going to suggest replace just that line with a flexable, like braided S/S, but if you have 50,000 on there with no problems your good to go!! TR
Two things of note regarding temps. First, the newer transmissions are designed to run at 150 degrees. Anythinng less and the steel moving parts will not mesh nicely with the aluminum valve body. Over a period of time bad things will happen. Second, get a non-contact temp gun. They are getting cheap now. If you suspect a wheel bearing, shoot it, weak cylinder, shoot the header. Valuable tool for troubleshooting.
I plan to install a transmission temp sensor, wired to a switch then to my water temperature gauge. Switch one way, water temp, switch the other way, trans temp. One gauge does both.
You will need to use a oil temp gauge as a WT one does not read high enough really. Most oil ones read to 325 and water only 265. And use a oil temp sender for the water also as they are specfic to either gauge.
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