12-27-2011, 08:43 PM | #1 |
Registered User
Join Date: Jun 2007
Location: Buda, Texas
Posts: 865
|
Turbo 400 or 350?
Looking at a '72 3/4 ton and trying to figure out the trans....what is the code on the spid for a turbo 350 and a turbo 400?
Thanks,
__________________
70chevytruck |
12-27-2011, 08:50 PM | #2 |
Registered User
Join Date: May 2011
Location: Lebanon, Mo.
Posts: 1,315
|
Re: Turbo 400 or 350?
Easiest way to tell fir me is a 350 wil have a kick down cable and 400 should have an electronic button. Also the modulator valve will face the rear on a 350 and the right side of the truck on the 400.
Posted via Mobile Device
__________________
1968 chevy lwb, getting ready to join forces with the 70 gmc 1970 gmc swb, getting ready to be a 68 chevy swb 1971 gmc lwb 2500 2wd Sierra Grande 1988 chevy 1-ton crew cab 2wd waiting for a 12v cummins |
12-27-2011, 09:30 PM | #3 |
Registered User
Join Date: Apr 2010
Location: McFarland CA
Posts: 1,392
|
Re: Turbo 400 or 350?
__________________
Pancho 69 c/10 step side 454/400 with 3.07 |
12-27-2011, 09:44 PM | #4 |
Vintage 4x4s
Join Date: Sep 2010
Location: Prior Lake, MN
Posts: 4,305
|
Re: Turbo 400 or 350?
The modulator faces left on my TH350
__________________
67 GMC K1500 Custom- 305V6 SM420, PTO, Ram Assist, yellow (the outcast) (project period correct upgrades) 67 GMC C2500 351V6 TH400, AC, PS, PB (can't decide what to do with. Update, decided to keep and will restore ) 86 CHV K30 502 th400, apple red NEW 71 CHV K20 350 SM465, ochre (saved work truck) 71 CHV K20 292 SM465, white, tach, PTO, (future project) 72 CHV K20 350 350th, medium blue (project stocker) 01 CHV K2500hd crew, indigo blue ^3 dont run and the others don't see winter either '86 K30 Cummins "Fireside" thread: http://67-72chevytrucks.com/vboard/s...d.php?t=649649 '71 K20 "get driveable" thread: http://67-72chevytrucks.com/vboard/s...d.php?t=590642 '72 K20 Build Thread: http://67-72chevytrucks.com/vboard/s...=493477&page=6 |
12-27-2011, 10:12 PM | #5 |
Registered User
Join Date: Sep 2005
Location: Canton North carolina
Posts: 3,079
|
Re: Turbo 400 or 350?
option cobe for both transmissions is the same m49. The only true way is to get underneath and look. Th350 has roughly a square pan and the 400 has a very irregularly shaped pattern.
__________________
67 blue step side- bb 68 gold and white swb cst anniversary 68 custom swb hot rod Ls swap 69 swb cst 6 cylinder/ overdrive 69 black/black cst bb swb 70 orange and white cst Canada built truck swb bb 71 black and white super swb bb 71 red and white super swb 72 green and white super swb 4x4 62 nova wagon 400 series Ls swapped 68 Camaro 327/4 speed- 1 owner, original paint 66 Volkswagen bettle 69 auto stick Volkswagen Beetle |
12-27-2011, 10:50 PM | #6 | |
Man of Mini-Talents
Join Date: Sep 2009
Location: Oklahoma City, OK
Posts: 4,295
|
Re: Turbo 400 or 350?
Quote:
The 400 pan is kinda shaped like Texas.
__________________
Steve Project - Ruth 66 Skylark Project - Lola 60 Biscayne Project - Iron Ox 54 GMC 100 Project - Darth 69 Camaro |
|
12-27-2011, 11:03 PM | #7 |
its all about the +6 inches
Join Date: Jan 2001
Location: Hilliard Ohio
Posts: 2,693
|
Re: Turbo 400 or 350?
most trucks got the same option number for 350 or 400 tranny as mentioned above... M49. A small handfull of trucks got mismarked M38 for the TH350.
Some will tell you the M49 was a TH350, and the M49* was a 400, but I call BS on that one personally. And for the nay sayers, TH350 was avalible on 10, 20 and 30 series trucks, not just the 10 series. |
12-27-2011, 11:16 PM | #8 |
Man of Mini-Talents
Join Date: Sep 2009
Location: Oklahoma City, OK
Posts: 4,295
|
Re: Turbo 400 or 350?
So, what options triggered the type of auto tranny you got? Getting the BB did it - anything else?
__________________
Steve Project - Ruth 66 Skylark Project - Lola 60 Biscayne Project - Iron Ox 54 GMC 100 Project - Darth 69 Camaro |
12-28-2011, 08:11 PM | #9 |
Registered User
Join Date: Sep 2005
Location: Canton North carolina
Posts: 3,079
|
Re: Turbo 400 or 350?
That is a good question and point on the m49 option. 3 of my trucks have the th400, but only my 71 bb truck has the little * beside the option code. The 68 only has m49 and the 70 only has m49. 70 was built in canada, 68 was built in baltimore and 71 was built in atlanta so dont think that makes a difference.
__________________
67 blue step side- bb 68 gold and white swb cst anniversary 68 custom swb hot rod Ls swap 69 swb cst 6 cylinder/ overdrive 69 black/black cst bb swb 70 orange and white cst Canada built truck swb bb 71 black and white super swb bb 71 red and white super swb 72 green and white super swb 4x4 62 nova wagon 400 series Ls swapped 68 Camaro 327/4 speed- 1 owner, original paint 66 Volkswagen bettle 69 auto stick Volkswagen Beetle |
12-28-2011, 08:36 PM | #10 |
Senior Member
Join Date: Aug 2003
Location: Lubbock, Texas
Posts: 2,443
|
Re: Turbo 400 or 350?
Even if the SPID reads M49, the firewall markings will read m38 if it is th350
__________________
72 Cheyenne Super 80 Silverado Blazer 2wd |
12-28-2011, 10:24 PM | #11 |
its all about the +6 inches
Join Date: Jan 2001
Location: Hilliard Ohio
Posts: 2,693
|
Re: Turbo 400 or 350?
The 68 & 68 trucks would not count in this discussion since the 400 was the only 3 speed.
Posted via Mobile Device |
Bookmarks |
|
|