OK, last question i ask about this trans, before tossing it in favor of a stick... after breaking one of the reverse-band linkages, and doing a full rebuild, i ***umed this problem was gone... but no, it's back again: After driving the car for an hour or so, 3rd begins to slip very badly. 2nd has no slipping at all, nor does first or reverse. It dosent do this every time, but often enough to really be annoying. Let the car sit for a while, and 3rd is nice and tight again. Any ideas? Oh, it's a 727, with a trans-go shift kit. Maybe 150 miles on it since this last rebuild... Other than that, the car is being a killer daily driver. Thanks!
That is exactly what 90% of all Mopar automatics I've ever owned or known about do...I believe it's nearly unavoidable for the most part!!! Ha Ha...you might want to check your TV (throttle valve) adjustment...if it's off, it'll cause that problem...if it's allowed to go out of adjustment long enough, you'll toast the ******. (I bought a 74 Roadrunner with an automatic that barely moved in reverse, and never got third...a throttle valve adjustment cured it's ills...but it was the RARE exception!) Strangely, I've found 904 ******s to be more forgiving and longer lasting than 727s...that, and the fact that 904s require less power to operate (and thus, generate less heat), makes me favor the 904 myself...if I just HAVE to run a Mopar auto ******!!
i set the TV so it's at full depression at WOT. with it any lower, the shift points were quite low. What is the proper way to set the TV? if it makes any difference, it's a '70 727 behind a 383. been wondering if there is something wrong with the pump... maybe not producing enough pressure??? When 3rd starts to slip, after that hour or so of driving, it's basically useless... anything much higher than just off idle in 3rd slips so badly, it's just like neutral. Let the car sit for an hour or two, and 3rd works just great for a while, again. weird. have i mentioned i hate automatics? oh, another thought... it's got the stock in-radiator cooler... could it be getting too hot, and causing this? also, it's running Type F... same as the 727 in my truck, from advise given by numerous people who know more about trannies than i do (which seems less and less every day). but ive had it in and out so many times, i can have it out and on my workbench in under 30 minutes now.
Dan, Sounds like you have a bad leak in the front clutch circuit. Could be a cut lip seal in the drum or apply piston. Check the sealing rings on the pump for leakage also. If you want, give me a call & I can coach you through it. (877)737-4438 toll free. Dave
I know the TV cable is set using a gauge to read line pressure, but I don't know the spec for your ****** off the top of my head...someone like Shifts here on the HAMB oughtta know that one. Every Mopar with an auto ****** that I've ever owned, except for TWO, did the exact same thing yours is doing! I bracket raced a Valiant one Summer, and after a full throttle p*** down the quarter, it would lose third gear and reverse! I'd make several time trials to get the trans hot, and then just run it like that all night! (If I let it cool down too much, third gear would come back and throw my consistency off...so after extended cool-down periods, I'd drop the shifter into second after it shifted there in Drive to keep it from hitting third! Then, I drove home every night in second gear cuz third and reverse would be GONE till next morning!) Hot Rod Magazine's cheap-o Dart project did the exact same thing. The fake Daytona used in "Joe Dirt" fried a 727 and was out of commission for most of the movie. In the newer "Dukes Of Hazzard" movie where they went to L.A., the General Lee puked a trans doing burnouts on WET pavement and they wrote the failure into the script! In one of the Power Tours, the only casualty was a Mopar with a blown auto ******! Too many local cases I know of to even list! It CAN'T be just coincidence...the failure rate of Mopar automatics is staggering compared to GM and Ford ratios! (I've only blown ONE GM automatic...a wimpy TH-250 after about three years of steady abuse and bracket racing in an old 79 Monte Carlo!) I feel for ya, Bud....I won't own a Mopar with an automatic anymore...unless a TH-400 or a Powerglide has been swapped into it!!!
Man, everything ive heard in the past about 727's is how indestructable they are... ive got two cars with them now, and nothing but problems with both... and NOW everyone tells me how many problems they have If the car wasnt actually my daily driver now, i'd just take the time to swap in a manual (which is really what i want, anyway). Come to think of it: anyone know if the crank on a 383 needs to be drilled for the pilot bushing? Might make the swap a bit quicker if not... im ***uming the driveshaft length will be different, too... flywheel, clutch, pressure plate, bellhousing, trans, shifter, clutch linkage... dont need THAT many parts... and it would beat the hell out of dropping the trans every week. Ive had this trans out so many times, i put a drain plug in the pan, just to make it easier on me. Shifts- thanks, ill give you a ring in a bit today or tomorrow! oh, how i had hoped it would be something simple that wouldnt require dropping the trans out again... Thanks guys!
Dan, Actually a 727 is a VERY tough ******. We have used them in drag cars for years. You must be very careful not to miss match parts tho. Dont give up on it yet, helps on the way. Dave
shifts- sent ya a PM... takin the trans out this weekend (i think)... lookin for a couple tricks with the valve body...
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