700r4 TC options

[BigBlue]

Hey Big time lurker here but hit a snag in my rebuild that eludes my simple mind

700r4 from a 83 6.2 k-5
I'm replacing the Torque converter just on principle after i witnessed the damage with my own eyes
I'm assuming any GM15 converters will match as long as i am running 27 splines
I would like to keep my stall low to mid as i will be driving this from Alaska to Kentucky in 6 months or so.

Anybody have a good gm standard number to give to my shop? While they are quite polite i just think they need some SME to get them going in the right directions

here are the appropriate measurements listed below but i cant figure out which would sit perfectly with the 6.2 or if all of them would run and just be different stall speeds this will be a daily driven vehicle with the occasional rowdy romp thrown in

# TC-GM15 Torque converter, 700r-4
Diameter - 12”, 298mm DIA. , PILOT - 1.703”, Mount - 3 Pads, Splines - 27
Notes - Medium Stall 1600-1800

# TC-GM15AF Torque converter, 700r-4
Diameter - 12”, 298mm, PILOT - 1.703”, Mount - 3 Pads, Splines - 27
Notes - Medium Stall, Brazed GM15

# TC-GM15AH Torque converter, 700r-4
Diameter - 12”, 298mm, PILOT - 1.703”, Mount - 3 Pads, Splines - 27
Notes - High Stall 1800-2000

# TC-GM15AHF Torque converter, 700r-4
Diameter - 12”, 298mm, PILOT - 1.703”, Mount - 3 Pads, Splines - 27
Notes - High Stall, Brazed GM15AH

# TC-GM15AL Torque converter, 700r-4
Diameter - 12”, 298mm DIA. , PILOT - 1.703”, Mount - 3 Pads, Splines - 27
Notes - Low Stall (1400-1600) Most Trucks, Vans

# TC-GM15-HP Torque converter, 700r-4
Diameter - 12”, 298mm, PILOT - 1.703”, Mount - 3 Pads, Splines - 27
Notes - High Stall (2100-2400) High Performance,

# TC-GM15S Torque converter, 700r-4
Diameter - 12”, 298mm, PILOT - 1.703”, Mount - 3 Pads, Splines - 27
Notes - Medium Stall (1600-1800)

 

[HotRodPC]

Being Diesel, I'd go low stall. Diesels make plenty of torque at low rpm, so they don't need alot of stall anyway. But, they also don't like high rpm. I'd even preffer a 1200-1400 for a 6.2, but this one should be sufficient. And yes, 27 spline input for 86 on down. 30 spline is for 87 and up.

# TC-GM15AL Torque converter, 700r-4
Diameter - 12”, 298mm DIA. , PILOT - 1.703”, Mount - 3 Pads, Splines - 27
Notes - Low Stall (1400-1600) Most Trucks, Vans

 

[BigBlue]

Thanks HotRod,

Appreciate the input now its just a matter of getting one of them up here in alaska.

 

[HotRodPC]

No Problem. I bet it's tough getting many things up there.

 

[bucket]

All my '85 and newer 700's have been 30 spline.

 

[HotRodPC]

Look at the ID #'s and see what year the trans is. The first digit will tell you what year the trans is.

 

[bucket]

Look at the ID #'s and see what year the trans is. The first digit will tell you what year the trans is.

Me? Yeah I know, the '85 and later were 30 spline. I've had a bunch of 86's too. '87 got a different valve body or something. I have a (well, had) couple '84 models and they are the 27 spline.

 

[HotRodPC]

I'd have to check my book again. I know the 87 and later got the auxillary valve body. I was also thinking it was only the 82-84 that had the 27 spline input shaft, but the converter site I looked up, showed them up to 87.

And now that I think of it, it may have been that the 85 up V8's got 30 splines and the V6 kept the 27 splines. This is why you gotta be careful with 700r4's and their transition years.

 

[bucket]

Yep, mine were all from behind V8's.

 

[BigBlue]

It's an 83 trans i went with your suggestion gm15al its all back in and doing okay now i just have to figure out why it wont shift into 3rd and i should be all good

 

[HotRodPC]

It's an 83 trans i went with your suggestion gm15al its all back in and doing okay now i just have to figure out why it wont shift into 3rd and i should be all good

How about 4th? Does it skip 3rd and go into OD, or doesn't get past 2nd?

This is a rebuilt trans right? #1, make sure the TV cable isn't to tight telling the trans to stay in passing gear. Then, next I'd have to wonder if the 3-4 clutch pack, piston and drum were all done right. Any mods to the valve body??? Shift Kit of any kind? Gotta run for now.

 

[BigBlue]

No 3rd or OD I built the trans myself all the seals were installed properly, all air checked they all held air and applied properly. I shift 1st to 2nd at roughly 16 mph then nothing goes to shift into 3rd and spikes RPM's. I replaced all clutches bands and seals on the rebuild, inspected all the hard parts for damage everything was solid. I "rebuilt" the governor new gear and cleaned the valve. I notced the seperator plate had some slight damage at the check ball locations since its been a few years i might have goofed a check ball as well. I did not pull the valve body apart that's the only thing i can think of is that a valve is sticking.

 

[HotRodPC]

No 3rd or OD I built the trans myself all the seals were installed properly, all air checked they all held air and applied properly. I shift 1st to 2nd at roughly 16 mph then nothing goes to shift into 3rd and spikes RPM's. I replaced all clutches bands and seals on the rebuild, inspected all the hard parts for damage everything was solid. I "rebuilt" the governor new gear and cleaned the valve. I notced the seperator plate had some slight damage at the check ball locations since its been a few years i might have goofed a check ball as well. I did not pull the valve body apart that's the only thing i can think of is that a valve is sticking.

I'd have to look at a chart to see what's holding and what's not for 3rd gear, but this sounds like a classic rookie mistake of putting a roller sprag on upside or backwards. Also, I don't recall which type the 700r4 has, to as if it's even possible to do it. But if you put a sprag on backwards/upside down and it grabs in one direction, but not the other, and you have the reversed, then that's what will cause the spin up when it looks for 3rd and can't make 3rd cuz it's spinning when it should be grabbing and holding. Talking about one of the one way clutches. I'm sure you know what I mean. Now I recall, you have 2 in this trans. 1 I think is for 2nd gear in the intermediates, then another in the Center Support that can only go in one way. But being this is a 4 speed instead of 3, that one I'm thinking about maybe for 3rd instead of 2nd. A missing check ball may do it, but doubtul a damaged check ball would do it. And yeah, a hung valve can do it for sure.

 

[BigBlue]

Before I pull the trans again and bust everything back down I might try to go full manual first. Been wanting to for a while now and I get the impression my valve body might be miffed up or my seperator plate check holes not sealing I dont think I installed any of the sprags wrong they only seemed to go in one way.

 

[BigBlue]

Great now im second guessing myself, I probably put it in backwards knowing my luck. is there anyway to tell right from wrong when instaling them I did check when I reinstalled and it locked up one way and free wheeled the other but i guess it was backwards most likely replace both sprags since I didnt in the begining.