Automatic tranny help

[lostfamilyof6]

Hi all,
I am pretty new to automatic transmissions. I need advice on a torque converter. I also need to know how to tell what tranny I have.

I just traded my 1992 ford superduty 2 wheel drive that I was going to convert to 4-wheel drive for a 1991 suburban. I did some research on it and it seems like I could have the Turbo 400 or the 700R? is this right if so how do I tell.

The guy I traded said it needed a new torque converter. Something is clanging really badly inside the torque converter but I know very little about automatics so is there an up grade for the original torque converter? I have seen them on line but mostly for street racing. I am wondering if someone could point me in the direction of a well-designed and bulletproof converter. If anyone out there could help I would really appreciate it.

Kendall

 

[chasespeed]

Is the trans overdrive or not? That'll tell ya... OD, 700

Look at your shift indicator...

P R N OD 2 1 700R4
P R N D 2 1 T400 or T350

Chase

 

[ntsqd]

Is the Sub a 1500 or a 2500? That will also indicate which is more likely to be under there.

Look underneath for confirmation. The 700R4 pan gasket rail shape is rectangular. The TH400 pan gasket rail shape is anything but rectangular.
TH400 pan:

If the converter is bad I would suggest having the trans gone thru while it is out, unless that was recently done by a reputable shop. Even then it may have had metal run through it due to the converter failing.

You might want to know about this company: http://www.bowtieoverdrives.com/index.shtml

 

[lostfamilyof6]

Thanks for the replies,

I think that it is a 700r4 as you both have pointed out I do have overdrive and the bottom is defiantly square.

I guess this is great news but I do feel like as long as I am going to pull it I may as well get a newer trans. this thing is a monster it has a 8 inch lift 38" tires TONS of clearance and I am thinking that the converter is probably shot due to heat (the fluid smells burnt)

Thanks for the link to the bowtie website. like I said I am new to automatics and this seems over my head so I guess farming this out is a necessity. I have rebuilt manuals before but this is a different beast.

Would anyone know how hard it would be to go ahead and put a modern 5 or even 6 speed manual in this beast? I would like the control and I wonder if it would get better MPG? Any thoughts or suggestions would be great.

BTW it is a 2500 barn doors TBI 350 runs strong, no body life all suspension, and right now it has some pretty worn out super swampers, I would love some ideas as to new tire choices as I am no a big fan of the swampers on trips (road noise is incredible I used to have them on a F350)

Thanks for any and all input.

 

[ccarley]

Sounds like quite a big Suburban!

If the gearing was not changed for the tires, then the trans may have been worked too hard & like you say, burned up the fluid & caused who knows what other damage.

I have a TH700R4 in my Suburban as well, and supposedly the previous owner did some mods to it. I like the way it shifts, it will pretty much be in the gear you want it to be in most of the time. If I need to shift it manually, I can still drop it down, no problem. I am not sure of the axle gears yet, however I'm pretty sure they are "low" because in 3rd at 60 (actual speed, 50 mph indicated speed) it's revving pretty high, with 35" BFG A/T's.

I'm not sure what tires are quiet in 38"... I hear the new BFG Mud's are nice though. The BFG A/T in 35" are nice, not too loud, and so far I've been pleased with the traction.

Good luck! How about some pics?

Clay

 

[shortbus4x4]

You should be able to do a NV4500 five speed conversion quite easily. Find a pickup or suburban from the same vintage that is a manual and take all the clutch stuff off of it. It will be a hydraulic setup. Don't forget the flywheel too. You will have to do a little adapting to get the NV4500 to work but Advance Adaptors will have the parts and know how to get it to work. If you stick with an auto make sure you have it gone through by a good rebuilder and get all the updates and HD parts added. Also make sure the TV cable is adjusted properly and add the biggest trans cooler you can.

 

[lostfamilyof6]

Thanks Clay, and shortbus

I am planning on doing a build thread starting here pretty quick once I decide to do with the tranny.

Clay, I am loving what you have done with yours but this one is rusted way too bad to bring it back to how nice yours looks.

My wife loves the idea of finally having an automatic (she is not a fan of driving in traffic with a clutch, but I am not sure I want to give up the control.
are automatics pretty good about downshifting on hills, etc? This thing is a beast and weighs a ton I don't want to loose control in the worse situations.

I have 4 kids and so right now just in the planning stages but I will post pics soon.

any other thoughts on the matter?

Thanks.

 

[shortbus4x4]

Talk to your trans rebuilder, tell them your concerns, they should be able to build you something that will work for you.

 

[bftank]

in regards to the clanking noise, i'm going to venture a guess that it's not the torque convertor but the flexplate. these crack on occasion, and when the crack flexes it can create a clanking noise. if the fluid smells burnt it has been overheated.

tire wise a 37x12.5 bfg all terrain is pretty quiet.

swap wise, 1500 to have the 700r4 rebuilt and updated,

1500 for rebuilt nv4500,
250 for clutch
100 for flywheel
100 for hydraulics
250 for drivelines
500 nickel and dime stuff

that being said the nv4500 is what i want in my sub, just something to think about. it can be done cheaper just depends on how resourceful you are.