The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 02-11-2008, 09:18 AM   #1
Chevy1972/GMC2000
Registered User
 
Join Date: Feb 2008
Location: British Columbia, Canada
Posts: 8
how to tell a th350 from a th400

I was just woundering if someone could tell me how to tell a turbo350 from a turbo400 trans. My trucks trans is option coded as a M49, what trans is that?
__________________
1972 k10 chevy lwb project.
2000 gmc 1500 4x4 reg/long
Chevy1972/GMC2000 is offline   Reply With Quote
Old 02-11-2008, 09:39 AM   #2
Palf70Step
State of Confusion!

 
Palf70Step's Avatar
 
Join Date: Jul 2002
Location: Gulfport, MS USA
Posts: 40,770
Re: how to tell a th350 from a th400

Looking at the shape of the pan is the easiet way.
Attached Images
 
__________________
Bill

1981 GMC High Sierra SWB Stepside

Member of Louisiana Classic Truck Club (LCTC)
Board Vendors
Bill's Gallery
Life isn't tied with a bow, but it's still a gift.
Live simply. Love generously. Care deeply. Speak kindly. Leave the rest to God!
It's scary when you start making the same noises as your coffee maker.
Palf70Step is offline   Reply With Quote
Old 02-11-2008, 11:28 AM   #3
cruiserman
Registered User
 
Join Date: Dec 2006
Location: Idaho
Posts: 210
Re: how to tell a th350 from a th400

400 oil pan is shaped like Texas.
__________________
72 C2500 LWB 402 Sierra Grande
05 Odyssey
08 Tundra
cruiserman is offline   Reply With Quote
Old 02-11-2008, 01:08 PM   #4
Longhorn Man
its all about the +6 inches
 
Longhorn Man's Avatar
 
Join Date: Jan 2001
Location: Hilliard Ohio
Posts: 2,700
Re: how to tell a th350 from a th400

quick and easy;
kick down cable = TH350
No kickdown cable = TH400
Longhorn Man is offline   Reply With Quote
Old 02-11-2008, 04:23 PM   #5
68350
Senior Member
 
68350's Avatar
 
Join Date: Jan 2002
Location: Williston, ND
Posts: 2,873
Re: how to tell a th350 from a th400

nother quick way,
th400-6 bolts in the tail housing
th350-4 bolts
__________________
68 Chevy CST/10, 50th Anniversary, 327/th400, 373 posi, buckets
68 GMC Shortbox Stepside, 402/th400, Tilt, Tach, Bucket Seats, 3.08 Positraction
69 Chevy Camaro SS, 383, 4 speed, positraction
70 Chevy El Camino SS396, Triple Black, 454/th400, Tach
70 Chevy Shortbox Stepside 4x4, 350/th350, Tilt, Tach, Cab Lights, Bumper Guards, Tow Hooks
70 Chevy 3/4 Longbox, 350/auto, 70k, SURVIVOR
71 Chevy Blazer, CST, 350/auto
71 GMC Sierra K2500, 454, 4 speed, 4.10 posi, 37s
71 Custom/30, Open Road, 350/th400, tilt
71 Chevy Cheyenne/20, 402/4 speed, tool and stowage
72 Chevy Shortbox Fleetside, 496 Stroker/th400, Tilt, Tach, Bucket Seats, 3.42 Posi
72 GMC Sierra Grande 2500. 427/th400, tilt, a/c, tool and stowage, buckets/console, 3.54 posi
72 GMC Sierra Grande Longhorn 2500. 402/th400, a/c, tool and stowage
68350 is offline   Reply With Quote
Old 02-11-2008, 04:30 PM   #6
Machinist1972
Registered User
 
Machinist1972's Avatar
 
Join Date: Feb 2008
Location: Langley B.C.
Posts: 38
Re: how to tell a th350 from a th400

The top right transmission in the picture is a turbo 400 transmission. I look to see where the modulator valve is. It should be on the passenger side closer to the front when looking at the transmission from the back.
Machinist1972 is offline   Reply With Quote
Old 02-11-2008, 04:32 PM   #7
BLE 'BURBAN
In the Forgotten far North.
 
BLE 'BURBAN's Avatar
 
Join Date: Jul 2007
Location: Anchorage, Alaska
Posts: 2,627
Re: how to tell a th350 from a th400

TH350 vacuum modulator faces right
TH400 Vacuum modulator faces back
__________________
1987 R3500 CREW CAB DUALLY (BIG RED)Acquired 06/12/2015
1990 chevy suburban V2500 5.7L
My cluster Mods-Nov 2007
overhead console Stereo install Round 2 Aug 2009
Heated/turn signal mirror upgrade
BLE 'BURBAN is offline   Reply With Quote
Old 02-11-2008, 05:42 PM   #8
72armyswbtruck
Registered User
 
72armyswbtruck's Avatar
 
Join Date: Feb 2004
Location: Idaho
Posts: 4,034
Re: how to tell a th350 from a th400

Boy look at all those ways to tell the difference
__________________
"Remember, They can Kill You, but they can't eat You, That's against the law!!!!!!!!!"
72armyswbtruck is offline   Reply With Quote
Old 02-11-2008, 05:56 PM   #9
blukangoo
Neighborhood Pickle Slinger
 
blukangoo's Avatar
 
Join Date: Jan 2007
Location: Cadolzburg, Bavaria, Germany
Posts: 2,222
Re: how to tell a th350 from a th400

Just like everyone else said:

TH350 has a Mechanical (cable) Detent Cable.
TH400 has an Electrical Detent Switch.

Easiest way is the shape of the drainpan.
Attached Images
  
__________________
--------------------------------------------------


My C10 Diary

Our cars:
1966 Chevrolet Chevelle 396 - TH350
1968 Chevrolet C10/CST 327 TH400/375
1969 Corvette Stingray 350 - Muncie Manual Trans
1969 Chevrolet ElCamino 350 - TH400
1970 Cutlass Supreme Convertible - 350 Rocket - TH350
1973 Camaro LT - New Engine Done - TH350

1973 Corvette Convertible 454 - TH400
blukangoo is offline   Reply With Quote
Old 12-01-2010, 11:52 PM   #10
LostMy65
But Found Her 25yrs Later!
 
LostMy65's Avatar
 
Join Date: Oct 2010
Location: Oregon City, Oregon
Posts: 9,398
Re: how to tell a th350 from a th400

Thanks for this thread. I now know I have a 350.
__________________
I lost my 65 - Found it 25 years later:
http://67-72chevytrucks.com/vboard/s...d.php?t=426650

66 C20 Service Truck:
http://67-72chevytrucks.com/vboard/s...d.php?t=428035
LostMy65 is offline   Reply With Quote
Old 12-06-2010, 01:53 PM   #11
blukangoo
Neighborhood Pickle Slinger
 
blukangoo's Avatar
 
Join Date: Jan 2007
Location: Cadolzburg, Bavaria, Germany
Posts: 2,222
Re: how to tell a th350 from a th400

Cool to know that people still read threads that are 2 years old.
__________________
--------------------------------------------------


My C10 Diary

Our cars:
1966 Chevrolet Chevelle 396 - TH350
1968 Chevrolet C10/CST 327 TH400/375
1969 Corvette Stingray 350 - Muncie Manual Trans
1969 Chevrolet ElCamino 350 - TH400
1970 Cutlass Supreme Convertible - 350 Rocket - TH350
1973 Camaro LT - New Engine Done - TH350

1973 Corvette Convertible 454 - TH400
blukangoo is offline   Reply With Quote
Old 03-26-2012, 11:05 PM   #12
JointTech
Registered User
 
JointTech's Avatar
 
Join Date: Feb 2012
Location: Mission Viejo, CA
Posts: 1,856
Re: how to tell a th350 from a th400

no 4 years old. I just found out i have a th400 Thanks.

mmmm thread necro
__________________
72 C20 Long Bed
SB350 TH400 14 bolt rear end
Extremely boring build thread
JointTech is offline   Reply With Quote
Old 09-17-2012, 02:57 PM   #13
dads longhorn
Registered User
 
dads longhorn's Avatar
 
Join Date: Mar 2010
Location: New mexico
Posts: 369
Re: how to tell a th350 from a th400

Thanks for the thread, now I know I have a 350 TH.
Is there a preference 350 vs 400? Thanks again
dads longhorn is offline   Reply With Quote
Old 03-17-2013, 04:29 PM   #14
catch2otwo
Registered User
 
Join Date: Mar 2013
Location: SF
Posts: 318
Re: how to tell a th350 from a th400

Anyone have a good recommendation of a deeper sump aluminum pan with a drain plug like the one pictured above?
catch2otwo is offline   Reply With Quote
Old 03-17-2013, 04:38 PM   #15
Tx Firefighter
Watch out for your cornhole !
 
Tx Firefighter's Avatar
 
Join Date: Jun 2003
Location: Texas
Posts: 14,059
Re: how to tell a th350 from a th400

Quote:
Originally Posted by catch2otwo View Post
Anyone have a good recommendation of a deeper sump aluminum pan with a drain plug like the one pictured above?
I've had a few of these over the years. They don't exactly give them away, but if you like quality, you've found the best.

http://mag-hytec.com/store/index.php...products_id=97
Posted via Mobile Device
Tx Firefighter is offline   Reply With Quote
Old 03-17-2013, 08:28 PM   #16
Palf70Step
State of Confusion!

 
Palf70Step's Avatar
 
Join Date: Jul 2002
Location: Gulfport, MS USA
Posts: 40,770
Re: how to tell a th350 from a th400

Here is what I used on MY T350
http://www.jegs.com/i/Hughes+Perform...FQzNnAodpGwAaQ
__________________
Bill

1981 GMC High Sierra SWB Stepside

Member of Louisiana Classic Truck Club (LCTC)
Board Vendors
Bill's Gallery
Life isn't tied with a bow, but it's still a gift.
Live simply. Love generously. Care deeply. Speak kindly. Leave the rest to God!
It's scary when you start making the same noises as your coffee maker.
Palf70Step is offline   Reply With Quote
Old 08-22-2016, 05:26 PM   #17
mrsmith
Registered User
 
Join Date: Jul 2016
Location: Fresno ,Ca
Posts: 8
Re: how to tell a th350 from a th400

I know this is a really old thread ,but it is still VERY useful to us that are not quite up to the level of some of you other guys . I figured out i have a TH350 thanks to this thread without breaking any kind of sweat. thank you everyone for sharing your knowledge.
mrsmith is offline   Reply With Quote
Old 08-22-2016, 10:26 PM   #18
factorystock
Registered User
 
factorystock's Avatar
 
Join Date: Feb 2007
Location: west coast
Posts: 2,584
Re: how to tell a th350 from a th400

Quote:
Originally Posted by Chevy1972/GMC2000 View Post
trans is option coded as a M49, what trans is that?
Ok, OP is long gone, however GM did cause some confustion by listing the same SPID code M49 for both "turbo hydramatics" in some years.
factorystock is offline   Reply With Quote
Old 08-22-2016, 11:02 PM   #19
GASoline71
"I ain't nobody, dork."
 
GASoline71's Avatar
 
Join Date: Sep 2007
Location: Whidbey Island, Washington
Posts: 8,745
Re: how to tell a th350 from a th400

But the SPID was telling the truth...

Gary
__________________
'cuz chicks dig scars...

My 1972 GMC 1500 Super Custom (Creeping Death) "long term" build thread.

The Rebuild of Creeping Death after the wreck

Quote:
Originally Posted by LONGHAIR View Post
I would never rebuild a 305.
Quote:
Originally Posted by prostreetC-10 View Post
I love using vacuum gauges as part of the carb tuning process. I hook the gauge to the inside of my garbage can and leave it there.
Quote:
Originally Posted by Marv D View Post
Remember Murphys 2nd law of mechanical relationships... "OPPOSING COMPONENTS ATTEMPTING TO OCCUPY THE SAME SPACE, AT THE SAME TIME, GENERALLY END UP OCCUPYING ADJOINING SPACE AT THE BOTTOM OF THE OIL PAN"
GASoline71 is offline   Reply With Quote
Old 02-04-2017, 04:55 PM   #20
Nachos82
Registered User
 
Join Date: Feb 2007
Location: Central Florida
Posts: 163
Re: how to tell a th350 from a th400

Right on fellas, and thanks blukangoo for the unmistakable picture of the two different pans.

Yea, this thread is old as crap, but it's the first Google search result that appears when you do "how to tell th350 from th400" and it was worth my efforts to log into the site and surf around like old times.

I got a camaro last month and was wondering if it had a th350 or th400. Figures the best truck forum out there had the answer to my question.

Upon deep investigation, if I had only waited 7 more days I could have made this a 9 year spread from initial post to my reply. Oh well, guess nobody can be that awesome.
Nachos82 is online now   Reply With Quote
Old 02-04-2017, 08:27 PM   #21
towbar
Registered User
 
towbar's Avatar
 
Join Date: Jul 2012
Location: Marshall, NC....heart of the Appalachians.....aka, Gods country!!
Posts: 509
Re: how to tell a th350 from a th400

another quick and easy......governor gear has a 4 bolt cover on a T400, a clip bail cover on a T350
towbar is offline   Reply With Quote
Old 06-20-2018, 04:55 PM   #22
hotwls13
Registered User
 
Join Date: Mar 2018
Location: Bakersfield, CA
Posts: 310
Re: how to tell a th350 from a th400

Quote:
Originally Posted by BLE 'BURBAN View Post
TH350 vacuum modulator faces right
TH400 Vacuum modulator faces back
Old thread but just read this. I have a 350 (according to PAN) and the Vacuum modulator faces back??? SO which is it??
Attached Images
  
hotwls13 is offline   Reply With Quote
Old 06-20-2018, 06:07 PM   #23
demian5
Registered User
 
demian5's Avatar
 
Join Date: Aug 2016
Location: Lake Forest, CA
Posts: 2,165
Re: how to tell a th350 from a th400

Quote:
Originally Posted by hotwls13 View Post
Old thread but just read this. I have a 350 (according to PAN) and the Vacuum modulator faces back??? SO which is it??
Yeah.... both clues tell you its a 350...
__________________
"Work hard, use your vacation days."
1970 C15 GMC Long Bed
1986 C20 Scottsdale
1983 K2500 Sierra Classic Suburban 6.2
Instagram: C10sofOC
demian5 is offline   Reply With Quote
Old 06-20-2018, 06:14 PM   #24
hotwls13
Registered User
 
Join Date: Mar 2018
Location: Bakersfield, CA
Posts: 310
Re: how to tell a th350 from a th400

Quote:
Originally Posted by demian5 View Post
Yeah.... both clues tell you its a 350...
It say's "TH400 Vacuum modulator faces back"

Unless I'm looking at it wrong, my 350 modulator faces BACK??
hotwls13 is offline   Reply With Quote
Old 06-20-2018, 06:42 PM   #25
geezer#99
Registered User
 
geezer#99's Avatar
 
Join Date: Aug 2009
Location: Bowser
Posts: 11,360
Re: how to tell a th350 from a th400

It doesn’t.
He was wrong.
Turbo 350 faces back.
Yours does.
geezer#99 is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 03:24 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, vBulletin Solutions Inc.
Copyright 1997-2013 67-72chevytrucks.com