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Speed limiter on 727 trans?

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74 D100 with a 318 and 727. When I hit 100 mph the trans felt like it went into neutral and the engine almost over revved on me. I let off the gas real quick but got on it again after dropping down to 90 and the trans acted normal and wanted to pull again. The engine nearly over revved from that so I dont feel like I want to try it again. Is there a speed limiter on the trans at 100? Or is it something worse. I have no problems shifting. My TV is set correctly. I had no burning smell or smoke. I might have a bit too much fluid in the transmission. My trans stick tube is bent funny (the wrong way due to a header install.. rookie mistake) so I cant check the level until I get another dipstick tube and bend it correctly for header clearance.
 
Fluid level or torque convertor are the only things I can think of off the top of my head . What RPM's were you running at that speed ?
 
Make sure throttle rod on transmission is adjusted correctly. If high mileage and transmission filter has never been changed may not be getting enough fluid to torque converter at high speed or could be a loss of governor pressure. The speed switch emissions has no affect directly to transmission functions.
 
Next thursday is payday again. I am planning on getting a Lokar braided stainless transmission dipstick and doing a fluid change. I have yet to put a gauge on the ports to check line pressures but I have the TV where I like the shifts to take place. I have no tack at the moment so I cant say what the RPM was at 100 mph. I am too curious to what that filter may look like, the trans is literally one of the last things Ill be touching since I got the truck back in March.
 
What's the fluid look like ? Red , no smell ? Brownish and stink's ?
 
I ordered an All Star Performance locking transmission dipstick tube and stick, got it installed and it didnt need to be bent in any way, it fits perfect along with the headers. Dropped the pan, maybe 3 to 4 quarts came out all together. It still had some color but not much. The filter look like it was made of metal mesh. Its stuffed full of worn down metallic dust. I think it was a combo of the low fluid and the clogged filter. I wont know until I finish putting it together.
 
I was able to get past 100 mph but the wind resistance didnt get me much faster than that. I still have the issue of the trans hesitating from a stop when it gets hot though. Ill sit at a light and when I try to go the trans will act like its in neutral til about 1200 rpm then it will feel like it was slammed into gear and it chirps the tires. I do not slip at all when I actually start going. And I shift just fine. Im thinking the torque converter might be worn or damaged slightly. I was planning on getting a 2400 stall converter anyways with a full manual valve body. I was talking to my transmission guy about a rebuild too later on this year.
 
Can you provide more info on slippage. Gear selector in D or 1? Does it slip in reverse? Unless some one has put it in you should not have a locking convert in your 74 and would not cause the problem you are in countering on take off anyway. A bad band or clutch pack would be more likely. There are much cheaper ways of improving 727 performance and should be done anyway before installing a manual valve body. Improved clutch pack and band materials, faster acting servo arms and Chrysler recommended valve body mods will gain more performance than a higher stall converter. The higher the stall the more heat generated if your RPM's at highway speeds are not over 2800 with a 2400 stall will not be long and all those new trans parts will be burnt up due to excessive heat. Just something to think about.
 
Yea I discussed all of that with my transmission guy. Easy to catch since he owns the shop across the street where I work. I can get away with a full rebuild that can handle the strip and reliable for daily driving. I said I would get the parts I wanted first before the rebuild so he Han slap them on. I plan on a high performance trans cooler with a fan, an aluminum deep sump trans pan from trick flow as well. I'm keeping the stock rear ratio. I rev about 3000 doing 70 mph.
 
Ah forgot to mention, zero slip in reverse, minimal slip in 3 and 2, and most of that hesitation slip in 1. It only does it when it gets hot. When its cold and first started it has zero slip what so ever.
 
Servo to rear band is going bad. Had same problem before replaced the servo and the problem went away.
 
Alright thanks. Im gonna get the goodies before I have it rebuilt so he can install them while its out and everything is clean. Until that time Ill have a couple of nice paper weights haha. I need to start organizing a build sheet. I just put in a MSD CD ignition system and its really nice.
 
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