transmission help - Tilted Forum Project Discussion Community

Fremen · 04-16-2005, 01:28 PM

I'd appreciate you guy's help with a friend's transmission trouble, if you please.

He has a 1983 half-ton Chevy pickup with a 454ci. engine with a 700r4 overdrive transmission, and the trans. is not shifting right.
He wants to go ahead and replace it, preferably with something that isn't an overdrive.

What he wants to know is if a 350th will replace the 700r4 without replacing the driveshaft?

He also needs to know if the 700r4 is the same length of the 350th, because he's trying to avoid changing the driveshaft.

Lastly, he needs to know the length of the 350th, powerglide, 400th, 700r4 and Muncie m20 4-speed transmission.

Do y'all know where to measure the trannie length from? Is it from the bell housing to the tailshaft, or somewhere else?

Thank you for any help you can provide.

lt1s10 · 04-16-2005, 05:16 PM

The 9 inch tailshaft length TH350 should fit in place of the 700r4. There is room in the yoke play for the difference in trans length. You will probably have to slot the trans crossmember mounting holes or re drill them because of the different trans mount locations.

Is he going to have to buy a TH350? If so I'd rebuild the 700r4 they can be built more then strong enough for a stock 454 and you'd still retain the overdrive which is really nice for long highway runs with gas prices the way they are.

Heck if I was close to you I'd give your friend a TH350 for his 700r4. I've got 3 backups and I'd like to have a 7004 to rebuild.

Fremen · 04-16-2005, 07:42 PM

Thanks for all your help, lt1s10.

J said that the chart helped him out a lot.

Yeah, he's going to buy a 350th if he can. He doesn't want the overdrive in the 700r4.
He's just wanting something to cruise into town and back, not for long trips.

He said he wishes you were closer, too.

It's been very troublesome finding the right trannie around here.

merkerguitars · 04-17-2005, 10:00 AM

Yeah overdrive wouldn't really be needed in a big block..it's gonna get bad gas mileage anyways, plus having a TH350 are nice, easier to find parts for and just easier to use since you wouldn't have the damnit overdrive. Modifying the rear cross member should be easy..they might even make adapter kits for such a project.

lt1s10 · 04-17-2005, 11:14 AM

Glad the chart was useful. I can't take credit for it though. I got it on a Vega site when I was looking for other info.

If he's going to be looking in junkyards for a core to rebuild the 9 inch tailshaft transmissions are most common in full size vans and pickups. I have also seen them in late 70s caprices.

Fremen · 04-17-2005, 01:32 PM

Thanks guys, I'll pass your ideas and advice on to him.
I do appreciate your help.

my knowledge of vehicles:
When asked to describe a car/truck, I usually say it was such & such color.

james t kirk · 04-17-2005, 04:51 PM

Interesting.

But if you were going to go to a Turbo 350, why wouldn't you opt for a 400?

My understanding is that they were made for the big blocks and are a heartier unit.

Scorps · 04-18-2005, 10:47 AM

Go for the TH400...I got one and it kicks ass

stingc · 04-18-2005, 11:09 AM

TH400's are notoriously inefficient. The only good thing about them is that they are really strong. A stock truck isn't going to need that strength, so going to a 400 over a 350 will just make it slower.

I don't really understand the aversion to overdrive. If you want to drive around without it most of the time, just leave the shifter in 3 instead of D/4.

Also, TH350's have a higher 1st gear than 700R4's, so your low speed acceleration will suffer. Then there's the extra fabrication needed to make a 350 fit. This doesn't seem like a very good idea.

james t kirk · 04-18-2005, 01:53 PM

Quote:

Originally Posted by stingc

TH400's are notoriously inefficient. The only good thing about them is that they are really strong. A stock truck isn't going to need that strength, so going to a 400 over a 350 will just make it slower.

I don't really understand the aversion to overdrive. If you want to drive around without it most of the time, just leave the shifter in 3 instead of D/4.

Also, TH350's have a higher 1st gear than 700R4's, so your low speed acceleration will suffer. Then there's the extra fabrication needed to make a 350 fit. This doesn't seem like a very good idea.

Interesting.

I also agree that Overdrive is a wonderful thing.

Out of curiousity, why are the 400's so inefficient?

james t kirk · 04-18-2005, 01:59 PM

http://www.montecarloss.com/SSThunder/drivetrain.html

Link to a great site discussing GM transmissions. Haven't had time to read it all.

stingc · 04-18-2005, 02:57 PM

Quote:

Originally Posted by james t kirk

Out of curiousity, why are the 400's so inefficient?

I don't know. But people who build engines all seem to say that they'll suck up a lot more power than pretty much any other transmission.

Nimisys · 04-18-2005, 06:37 PM

they are built big and heavy. a lot of rotating mass in comparison with the th350, the 200r4 and the 700r4. they can take a shitload more abuse however. thats why you saw them behind bigblocks and cadillacs until those engines got nuetered.

Scorps · 04-20-2005, 10:32 AM

Quote:

Originally Posted by stingc

TH400's are notoriously inefficient. The only good thing about them is that they are really strong. A stock truck isn't going to need that strength, so going to a 400 over a 350 will just make it slower.

I don't really understand the aversion to overdrive. If you want to drive around without it most of the time, just leave the shifter in 3 instead of D/4.

Also, TH350's have a higher 1st gear than 700R4's, so your low speed acceleration will suffer. Then there's the extra fabrication needed to make a 350 fit. This doesn't seem like a very good idea.

Well my TH400 isn't slow.

But it does have a shift kit!

IanSturgill · 05-02-2005, 06:42 AM

Yeah, the TH400 is a badass transmission, with a little help

Fremen · 05-02-2005, 08:55 PM

New questions, please:

My friend was wondering how many gears the 4L80E has, and if it is an automatic transmission or a standard one?

Martian · 05-02-2005, 11:08 PM

4L80E is closely related to the TH400, but on top of the turbo 400's 3 gears it has a fourth (overdrive) gear. It's an automatic.

EDIT - you may run into trouble if you try to stick a 4L80E in that truck. If I remember right it's electronically controlled and runs off the engine's computer. If you don't need the OD, a TH400 might be the better option of the two.

So, yeah. If you want a new tranny other than a 700r4 I'd say your options are a TH350 or TH400. I'd go with the 400 because it's tough as all hell, but if you're leaving the engine stock and don't plan on driving it too hard the 350 might be the better choice.

lt1s10 · 05-02-2005, 11:14 PM

In most of the 4L80E versions shifting is computer controlled. If he doesn't have a computer controlled engine that can also control the trans then it's probably more work then it's worth to swap in the 4L80E. They also sell stand alone ecu's for just the trans but they are pricy. The 4L80E is common in the heavy duty GM trucks and also in the motorhome and utility chasis kits that GM sells. There are non computer controlled versions of the 4L80E but they are not very common at least where I am.

How much money is he thinking about spending? If he's trying to do it on the cheap his best bang for the buck would be to build the 700R4 he has already since it seems he's having a hard time getting a hold of either a TH350 or TH400. During a rebuild the 700R4 can be made strong enough to handle the 454 unless he's already built the heck out of that 454 or he's running forced induction.

Nimisys · 05-03-2005, 05:59 PM

Quote:

Originally Posted by lt1s10

In most of the 4L80E versions shifting is computer controlled. If he doesn't have a computer controlled engine that can also control the trans then it's probably more work then it's worth to swap in the 4L80E. They also sell stand alone ecu's for just the trans but they are pricy. The 4L80E is common in the heavy duty GM trucks and also in the motorhome and utility chasis kits that GM sells. There are non computer controlled versions of the 4L80E but they are not very common at least where I am.

ALL 4l80E require a TCM to function. thats what the E stands for, Electronic. Not all TCM's have to be made by GM though to function correctly. BUT you still must have a TCM.

currently market prices put a running 4l80e setup at over 2grand to implement, with a used tranny.

they did add a 4th direct clutch on top of the th400 to produce an overdrive gear. they are similar, but built beefier. they weigh in close to 225lbs dry.

lt1s10 · 05-04-2005, 02:41 AM

Quote:

Originally Posted by Nimisys

ALL 4l80E require a TCM to function. thats what the E stands for, Electronic. Not all TCM's have to be made by GM though to function correctly. BUT you still must have a TCM.

currently market prices put a running 4l80e setup at over 2grand to implement, with a used tranny.

they did add a 4th direct clutch on top of the th400 to produce an overdrive gear. they are similar, but built beefier. they weigh in close to 225lbs dry.

I seen these 4L80E transmissions used in tractor pull rigs before.

http://www.transmissioncenter.net/4L80E.htm

Also seen a 4L80E trans built by Hughes Performance (I think) without the electronics used in a 71 Chevelle and I got to look at that car on a lift. It looked like the 4L80E and there wasn't a computer with it either. Definitely no harness and no electrical at all except for the speedo gear output.

I'm not real sure how they get around the electronics. If it's just a fully manual valve body or how they do it. And they aren't cheap either.

Fremen · 05-04-2005, 06:50 PM

Another couple of questions, please.

How much fluid does the 350th hold,
and does the 350th flywheel interchange with the 700r4?

merkerguitars · 05-04-2005, 08:22 PM

Here is a handy chart...

Size of Converter(stock pan) Number of Quarts

13" 5

12" 4

11" 3-1/2

10" 3

9" 2-1/2

8" 2

7" 2

Transmission No. of quarts

GM TH350 4

GM TH400 6

GM Powerglide 4

GM 700R4/4L60E 6

GM 2004R 6

GM 4L80E 7.7

TF 727 5

TF 904 5

Ford C4 5-1/2

Ford C6 7

Ford AOD/AODE 6-1/2

Fremen · 05-04-2005, 08:36 PM

Thanks for the info, merker. Justin said it helped him out.

Do you happen to know anything about the flywheels, as well?

Thanks for any help you can give.

04-16-2005, 01:28 PM	#1 (permalink)
Fremen With a mustache, the cool factor would be too much Location: left side of my couch, East Texas	transmission help I'd appreciate you guy's help with a friend's transmission trouble, if you please. He has a 1983 half-ton Chevy pickup with a 454ci. engine with a 700r4 overdrive transmission, and the trans. is not shifting right. He wants to go ahead and replace it, preferably with something that isn't an overdrive. What he wants to know is if a 350th will replace the 700r4 without replacing the driveshaft? He also needs to know if the 700r4 is the same length of the 350th, because he's trying to avoid changing the driveshaft. Lastly, he needs to know the length of the 350th, powerglide, 400th, 700r4 and Muncie m20 4-speed transmission. Do y'all know where to measure the trannie length from? Is it from the bell housing to the tailshaft, or somewhere else? Thank you for any help you can provide. __________________ Google

04-16-2005, 05:16 PM	#2 (permalink)
lt1s10 Crazy	The 9 inch tailshaft length TH350 should fit in place of the 700r4. There is room in the yoke play for the difference in trans length. You will probably have to slot the trans crossmember mounting holes or re drill them because of the different trans mount locations. Is he going to have to buy a TH350? If so I'd rebuild the 700r4 they can be built more then strong enough for a stock 454 and you'd still retain the overdrive which is really nice for long highway runs with gas prices the way they are. Heck if I was close to you I'd give your friend a TH350 for his 700r4. I've got 3 backups and I'd like to have a 7004 to rebuild. Last edited by lt1s10; 04-16-2005 at 05:20 PM..

04-16-2005, 07:42 PM	#3 (permalink)
Fremen With a mustache, the cool factor would be too much Location: left side of my couch, East Texas	Thanks for all your help, lt1s10. J said that the chart helped him out a lot. Yeah, he's going to buy a 350th if he can. He doesn't want the overdrive in the 700r4. He's just wanting something to cruise into town and back, not for long trips. He said he wishes you were closer, too. It's been very troublesome finding the right trannie around here. __________________ Google

04-17-2005, 10:00 AM	#4 (permalink)
merkerguitars Buffering......... Location: Wisconsin...	Yeah overdrive wouldn't really be needed in a big block..it's gonna get bad gas mileage anyways, plus having a TH350 are nice, easier to find parts for and just easier to use since you wouldn't have the damnit overdrive. Modifying the rear cross member should be easy..they might even make adapter kits for such a project. __________________ Donate now! Ask me How! Please use the search function it is your friend. Look at my mustang please feel free to comment! http://www.tfproject.org/tfp/showthread.php?t=26985

04-17-2005, 01:32 PM	#6 (permalink)
Fremen With a mustache, the cool factor would be too much Location: left side of my couch, East Texas	Thanks guys, I'll pass your ideas and advice on to him. I do appreciate your help. my knowledge of vehicles: When asked to describe a car/truck, I usually say it was such & such color. __________________ Google

04-17-2005, 11:14 AM	#5 (permalink)
lt1s10 Crazy	Glad the chart was useful. I can't take credit for it though. I got it on a Vega site when I was looking for other info. If he's going to be looking in junkyards for a core to rebuild the 9 inch tailshaft transmissions are most common in full size vans and pickups. I have also seen them in late 70s caprices.

04-17-2005, 04:51 PM	#7 (permalink)
james t kirk Junkie Location: Toronto	Interesting. But if you were going to go to a Turbo 350, why wouldn't you opt for a 400? My understanding is that they were made for the big blocks and are a heartier unit.

04-18-2005, 10:47 AM	#8 (permalink)
Scorps Lost!! Location: Kingston, Ontario	Go for the TH400...I got one and it kicks ass

04-18-2005, 11:09 AM	#9 (permalink)
stingc Psycho Location: PA	TH400's are notoriously inefficient. The only good thing about them is that they are really strong. A stock truck isn't going to need that strength, so going to a 400 over a 350 will just make it slower. I don't really understand the aversion to overdrive. If you want to drive around without it most of the time, just leave the shifter in 3 instead of D/4. Also, TH350's have a higher 1st gear than 700R4's, so your low speed acceleration will suffer. Then there's the extra fabrication needed to make a 350 fit. This doesn't seem like a very good idea.

04-18-2005, 01:59 PM	#11 (permalink)
james t kirk Junkie Location: Toronto	http://www.montecarloss.com/SSThunder/drivetrain.html Link to a great site discussing GM transmissions. Haven't had time to read it all.

04-18-2005, 06:37 PM	#13 (permalink)
Nimisys Crazy Location: San Diego	they are built big and heavy. a lot of rotating mass in comparison with the th350, the 200r4 and the 700r4. they can take a shitload more abuse however. thats why you saw them behind bigblocks and cadillacs until those engines got nuetered.

05-02-2005, 06:42 AM	#15 (permalink)
IanSturgill Crazy Location: Lex Vegas, KY	Yeah, the TH400 is a badass transmission, with a little help

05-02-2005, 08:55 PM	#16 (permalink)
Fremen With a mustache, the cool factor would be too much Location: left side of my couch, East Texas	New questions, please: My friend was wondering how many gears the 4L80E has, and if it is an automatic transmission or a standard one? __________________ Google

05-02-2005, 11:08 PM	#17 (permalink)
Martian Young Crumudgeon Location: Canada	4L80E is closely related to the TH400, but on top of the turbo 400's 3 gears it has a fourth (overdrive) gear. It's an automatic. EDIT - you may run into trouble if you try to stick a 4L80E in that truck. If I remember right it's electronically controlled and runs off the engine's computer. If you don't need the OD, a TH400 might be the better option of the two. So, yeah. If you want a new tranny other than a 700r4 I'd say your options are a TH350 or TH400. I'd go with the 400 because it's tough as all hell, but if you're leaving the engine stock and don't plan on driving it too hard the 350 might be the better choice. Last edited by Martian; 05-02-2005 at 11:11 PM..

05-02-2005, 11:14 PM	#18 (permalink)
lt1s10 Crazy	In most of the 4L80E versions shifting is computer controlled. If he doesn't have a computer controlled engine that can also control the trans then it's probably more work then it's worth to swap in the 4L80E. They also sell stand alone ecu's for just the trans but they are pricy. The 4L80E is common in the heavy duty GM trucks and also in the motorhome and utility chasis kits that GM sells. There are non computer controlled versions of the 4L80E but they are not very common at least where I am. How much money is he thinking about spending? If he's trying to do it on the cheap his best bang for the buck would be to build the 700R4 he has already since it seems he's having a hard time getting a hold of either a TH350 or TH400. During a rebuild the 700R4 can be made strong enough to handle the 454 unless he's already built the heck out of that 454 or he's running forced induction. Last edited by lt1s10; 05-02-2005 at 11:24 PM..

05-04-2005, 06:50 PM	#21 (permalink)
Fremen With a mustache, the cool factor would be too much Location: left side of my couch, East Texas	Another couple of questions, please. How much fluid does the 350th hold, and does the 350th flywheel interchange with the 700r4? __________________ Google

05-04-2005, 08:22 PM	#22 (permalink)
merkerguitars Buffering......... Location: Wisconsin...	Here is a handy chart... Size of Converter(stock pan) Number of Quarts 13" 5 12" 4 11" 3-1/2 10" 3 9" 2-1/2 8" 2 7" 2 Transmission No. of quarts GM TH350 4 GM TH400 6 GM Powerglide 4 GM 700R4/4L60E 6 GM 2004R 6 GM 4L80E 7.7 TF 727 5 TF 904 5 Ford C4 5-1/2 Ford C6 7 Ford AOD/AODE 6-1/2 __________________ Donate now! Ask me How! Please use the search function it is your friend. Look at my mustang please feel free to comment! http://www.tfproject.org/tfp/showthread.php?t=26985 Last edited by merkerguitars; 05-04-2005 at 08:26 PM..

05-04-2005, 08:36 PM	#23 (permalink)
Fremen With a mustache, the cool factor would be too much Location: left side of my couch, East Texas	Thanks for the info, merker. Justin said it helped him out. Do you happen to know anything about the flywheels, as well? Thanks for any help you can give. __________________ Google