Gearing Issues Maybe ?

[80Cutty]

Hello
I Have A 1980 Cutlass With A 455 Olds, OIds Th350, 81 Monte Carlo Rear End. My Car Shifts Into 3rd And Starts Revving Up At 40 45 mph The Rpms Just Gets Higher And Higher And I Finally Did Some Damage Blew Out A Brand New Freeze Plug The One On The Drivers Side To The Front Of The Motor I'm Trying To Figure Out Whats Wrong Please Help !?!?

 

[DRIVEN]

Huh?

 

[ReQ]

not trying to come across as a jerk or a know it all, but maybe you should study a little on how gear ratios work, specifically ring and pinions in a rear end, then venture over to the automatic transmission, I suggest "howstuffworks" for a start

also, my vote is transmission needs to be rebuilt but i am far from an expert

and the only time I have ever seen a freeze plug actually blow out of a block was an improperly installed freeze plug, high RPMs and namely heat will cause higher water pressure in a block, but theoretically many other things should blow before a freeze plug unless you do not get it installed correctly, but hey I learned my lesson!.. now I install them properly

 

[79malibubbctt]

Its either the bands in the transmission slipping or the converter messing up. Pull the pan and do a filter and oil change. That might help if the bands arent to far gone. The rearend will never slip like that.

 

[80Cutty]

I Just did a fresh oil change and transmission fluid change 200 miles ago and both filters were changed, oil and transmission. I know why a freeze plug goes but when your trying to drive 30 miles at 3500 rpms going 45 in a 55 zone you have no choice but to keep your foot into it. I'm Just Trying To Figure Out Why It Didn't Do This When I Had my v6 in the car with the same transmission and rear end. i never touched the transmission with any parts besides the maintenance. the transmission shifts real smooth into gears but at 35 it shifts into 3rd then at 45 it acts like it wants to shift again but you have no more gears to shift into.

 

[DRIVEN]

You either AREN'T going into 3rd or the transmission is slipping like mad. If you are spinning at 3500rpm at 45mph it doesn't sound like you've made it into 3rd yet. Is the modulator hose attached? Is the kickdown cable pulled too tight?

 

[80Cutty]

You either AREN'T going into 3rd or the transmission is slipping like mad. If you are spinning at 3500rpm at 45mph it doesn't sound like you've made it into 3rd yet. Is the modulator hose attached? Is the kickdown cable pulled too tight?

I Cut The KickDown cable because i caught it on fire so i cut the whole burnt part off and the kick down cable can be pulled out and retracts by itself and it shifts into third because i feel it and i shifted it manually

 

[Bonnewagon]

Replace it. It's a lot more than a kickdown cable, it is a transmission control. You are excluding the trans from your throttle position data and it doesn't know what to do. Before you said that, I thought the Governor may be sticking, but fix that cable first.

 

[80Cutty]

Replace it. It's a lot more than a kickdown cable, it is a transmission control. You are excluding the trans from your throttle position data and it doesn't know what to do. Before you said that, I thought the Governor may be sticking, but fix that cable first.

but i can pull the cable out and it retracts by itself that really shouldn't be the problem but who knows ill try and see this weekend i have to work all week and replace that freeze plug what a pain that's gonna be :!:

 

[DRIVEN]

I'm pretty sure that the cable is for passing gear only on a TH350. Could be wrong though. My thought was that it was pulled too tight. Guess that's not the case. There seems to be more to your story. Engine swap and fire? What's the history? Did this start immediately after other work was done or just happen out of the blue?