mooses3
New member
- 7
- 1
- 3
- Location
- Monett, MO.
I have M1009 that I would like replace TH400 transmission with a 700R4 transmission and need to know what torque converter and flywheel flex plate to use and where to purchase.
-
Steel Soldiers now has a few new forums, read more about it at: New Munitions Forums!
Replacing TH400 Tranny with 700R4 in M1009
- Thread starter mooses3
- Start date
Barrman
Well-known member
- 5,274
- 1,796
- 113
- Location
- Giddings, Texas
It is your truck to do as you wish.
Why are you swapping? I ask because with the 3.08:1 axle gears a deep overdrive like the 700R4 really doesn't do you any good unless you are over 75-80 mph.
There is a diesel torque converter that the 700R4 used with the 6.2. The flexplate I believe is the same.
Do you have the 6.2-400R4 cable bracket?
Why are you swapping? I ask because with the 3.08:1 axle gears a deep overdrive like the 700R4 really doesn't do you any good unless you are over 75-80 mph.
There is a diesel torque converter that the 700R4 used with the 6.2. The flexplate I believe is the same.
Do you have the 6.2-400R4 cable bracket?
- 3,752
- 1,529
- 113
- Location
- North Carolina - FINALLY !
I am interested because I have a set of 3:42 axles that I also want to swap in.
Barrman
Well-known member
- 5,274
- 1,796
- 113
- Location
- Giddings, Texas
Figured that was your plan but wanted to ask.
Just look up the part numbers for flexplate and converter that go into a 1988 or 1989 6.2 Suburban 1/2 ton. That should give you the right ones.
Just look up the part numbers for flexplate and converter that go into a 1988 or 1989 6.2 Suburban 1/2 ton. That should give you the right ones.
2INSANE
Well-known member
- 725
- 825
- 93
- Location
- Belgrade, Montana
I would not do a 700r4 in your M1009 unless you have a minimal of 3.73 gears. I have 4.56 in mine and am currently in the process of doing the swap.
If you do the swap, you will Benifit from a pre 1986 700r4 because it has a manual valve body inside that does not require an electrical switch for the lockup.
Your current flexplate will work with a 3 bolt 1200-1400 stall torque converter you will need.
Also you will need to spend big bucks getting both 700r4 and transfer case rebuilt with the 32 spline shafts instead of the 27 spline to handle the torque of the diesel better. Here’s my current cost of doing the swap…
Junkyard 700r4 Core $300
700r4 Rebuild with the best of the best parts $1700
Junkyard Np208 core with correct spline $225
Np208 Rebuild $700
Junkyard crossmember, support brace, shifting linkage and other hardware $75
Kickdown Cable new from EBay $56
Dont forget to add labor to remove and replace and additional costs for the drive shafts to be shortened and lengthened and cost of fluids and gaskets/rtv.
Honestly, a nv4500 or 4l80e would be stronger and much cheaper if you want the extra gears.
Note: Every hour on the hour, I question my financial sanity with my choice of doing this 700r4 swap. After it is all said and done here in the near future, my sanity might change while passing people up at 80mph getting 18+mpg.
If you do the swap, you will Benifit from a pre 1986 700r4 because it has a manual valve body inside that does not require an electrical switch for the lockup.
Your current flexplate will work with a 3 bolt 1200-1400 stall torque converter you will need.
Also you will need to spend big bucks getting both 700r4 and transfer case rebuilt with the 32 spline shafts instead of the 27 spline to handle the torque of the diesel better. Here’s my current cost of doing the swap…
Junkyard 700r4 Core $300
700r4 Rebuild with the best of the best parts $1700
Junkyard Np208 core with correct spline $225
Np208 Rebuild $700
Junkyard crossmember, support brace, shifting linkage and other hardware $75
Kickdown Cable new from EBay $56
Dont forget to add labor to remove and replace and additional costs for the drive shafts to be shortened and lengthened and cost of fluids and gaskets/rtv.
Honestly, a nv4500 or 4l80e would be stronger and much cheaper if you want the extra gears.
Note: Every hour on the hour, I question my financial sanity with my choice of doing this 700r4 swap. After it is all said and done here in the near future, my sanity might change while passing people up at 80mph getting 18+mpg.
Last edited:
reloader64
Active member
- 377
- 138
- 43
- Location
- Liberty Hill, Texas
If you will be using stock size tires, the 3.42 gear and 700R4 combo will work ok. I put 33 inch tires on my wife's civvy Blazer (3.42 from the factory) with the 700R4, and it was a dog. I went to 3.73 gears, and that helped. The beloved 6.2 diesel just doesn't have enough torque to drag around a high overall gear ratio. Even with the 3.73 gear in my wife's truck, I usually drive around town in 3rd gear. It goes 70 mph pretty well, though.
Scott
Scott
Good afternoon all, purchased a 86 m1009 a few months ago, just rebuilt the t400 completely. I've been reading on the forums about how the m1009 came with 3.08 gears. Mine clearly did not as my truck does like anything past 55 or 60, leading me to believe it has 4.56s. Whats the benefit of a 700r4 conv. And if I'm to keep my t400, what gears would you recommend for it not to scream at me on the hwy?
2INSANE
Well-known member
- 725
- 825
- 93
- Location
- Belgrade, Montana
Read this first…
The One Stop 700R4 Swap M1009
Overview Please give many thanks to the 10+ SS members for giving me the motivation to create this thread. Chuckg, 4sdair, forest522, computer54, dezertdemond, Dsilverline, Chevymike, ssdvc, TheMod, Mullaney, royalflush55, 1love, Sharecropper… By popular demand! This is a REAL M1009 1984...
www.steelsoldiers.com
700r4/np208, 4.56 gears and 37” tires, I get up to 80mph and it is still not screaming.
U should Do the nv4500 or 4l80e swap. Much cheaper and stronger.
Last edited:
Good read!!! Thank you! Maybe after my t400 pops as i just dumped a bunch of money into the rebuild. Would i be ok swapping out to the 3.08 gears or go to a 3.73 gear, maybe ill test a 3.42 and do a writeup