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gmc-rob · 05-06-2002, 09:33 AM

Since all you guys seem to know so much about these trucks, what is the difference between a TH350 and TH400 and which on is more desirable. I know the 400 can take more torque than the 350 but which one would you rather have in your truck? Thanks Rob

tom hand · 05-06-2002, 10:10 AM

I have always liked t-350's never had a problem with one. Unless you have a lot of money you can't build a smallblock stout enough to hurt one. If you are doing major towing or have a killer bigblock then it might be time to step up to a 400. Just keep in mind that a 400 uses more horsepower to do it's automatic thing, so you don't want to use one unless you have to.

------------------
72 GMC Sierra SWB almost finished---- 84 Softail
Olive Branch MS

slam33 · 05-06-2002, 10:11 AM

If you have a SB in front of it, go with the 350. There reliable, stong, and have a higher first gear. The 400 will take a bit more torque but it will cost you about 30 hp to spin it. You can build a 350 to handle 500 flbs. The TH400 was more intended for the a BB becuse of the larger low end torque it puts out.

------------------
71 basic C-10 350. The only option is the rust.No nothing on it, but thats all about to change. <A HREF="http://www.geocities.com/stevemau/slam33page.html?1004806705410

" TARGET=_blank>http://www.geocities.com/stevemau/slam33page.html?1004806705410

</A>

**fine69** · 05-06-2002, 11:11 AM

I hate to tell you this but, , Tons of these trucks were built with T400's behind smallblocks. I have owned several. Mostly 3/4 ton trucks. But i have seen 1/2 tons with the T400, and even a 1/2 ton 68 panel with a 327/T400 factory.
I will take a T400 any day over a T350. I do tow alot though.

**COBALT** · 05-06-2002, 11:53 AM

My '69 C20 came stock with a 350 4bolt main in front of a TH400. I simply love it. Strong and reliable. I like it so much in fact that I'm going to rebuild another TH400 and set up a work truck to have the same setup.

One thing to consider is the availability of used TH400s. There's not a lot of Chevy cases left. Even if you prefer the TH350 its something to think about.

------------------
'69 3/4 ton C20 2wd w/ 350ci/400THM and a wood bed!
'69 3/4 ton Custom 20 2wd w/ ORIGINAL 350ci/4sp Manual and a wood bed (parts beast).
Seattle, WA.

*See pics of my trucks and project at www.webshots.com!

*Fast68Chevy* · 05-06-2002, 02:28 PM

fine69, thats cuz 350 did not exist til 69,, only in maro in 68 was there th350 earlier than 69

[This message has been edited by Fast68Chevy (edited May 06, 2002).]

Woody · 05-06-2002, 02:44 PM

My truck still has the orginal T400 in it. It has not been rebuilt that I can tell. I have towed/hauled/hot rodded the hell out of it and it has almost 200k miles on it and still going.....it has been serviced (filter and fluid changed) a couple times. They are tough to beat. I hope to go to a 700R4 soon for gas milage...

------------------
Woody
'69 Custom-10 Deluxe
Short Fleetside,Factory 350cid/TH400,A/C,PS,PB,Carpet
Coming soon 700R4, 350 Crate Engine, Pwr Disks...

Longhorn Man · 05-06-2002, 07:22 PM

I swear by the TH350. like said before...it'll take lots of money into your engie to kill a TH350.

------------------
'69 G.M.C. 350/350. Trying to clean up the left over damage from the Dope-Smokin-Old-Man
I've been dubbed the Longhorn Freak/Fanatic/Expert, I just hope I can live up to it.
FINALLY got the HORNIAC...a '70 one ton Longhorn with a Pontiac 350/350 and lots of 'personality'. Check out The Longhorn Webite.
If you need a pic posted, E-mail me at longhornmail@yahoo.com
Andy, in Columbus Ohio

dmnall · 05-06-2002, 10:01 PM

Nothing wrong with either TH350 or TH400, just the fact that TH400 can take more abuse! If I could justify the cost, I would put a 4L80E tranny in my truck for Overdrive but the problem is this tranny requires a $ 2000 conversion kit to work with Older Trucks that did not have computers in them! Just realize when you do put a 700R4 in and you decide to tow with that tranny or even driving up a large Grade or Hill, Take it out of Overdrive, or you will see how weak a 700R4 will become!! I am currently running a TH400 and I plan to put in a Bowtie Overdrive 700R4 and I will be taking precautions when driving up Hills and Towing with it because I don't want a Dead Tranny on my hands !!
This is just my opinion though !!

------------------
Truck #1 68 Chev LWB Fleet w/ Wood Floor (Sucks Gas and Hauls Ass!) and in process of Body Work...

Truck #2 1994 GMC Sierra SL w/ 4.3L Vortec V6, 4L60E Auto!!

Longhorn Man · 05-06-2002, 10:08 PM

If you want an indestructable overdrive, visit this site; http://www.gearvendors.com/commercial.html

------------------
'69 G.M.C. 350/350. Trying to clean up the left over damage from the Dope-Smokin-Old-Man
I've been dubbed the Longhorn Freak/Fanatic/Expert, I just hope I can live up to it.
FINALLY got the HORNIAC...a '70 one ton Longhorn with a Pontiac 350/350 and lots of 'personality'. Check out The Longhorn Webite.
If you need a pic posted, E-mail me at longhornmail@yahoo.com
My name is Andy...not Randy...I'm in Ohio...Not Illinois...close enough?
Columbus Ohio

05-06-2002, 10:11 AM	#3
slam33 Registered User Join Date: Aug 2001 Location: Long Beach, Ca Posts: 1,432	If you have a SB in front of it, go with the 350. There reliable, stong, and have a higher first gear. The 400 will take a bit more torque but it will cost you about 30 hp to spin it. You can build a 350 to handle 500 flbs. The TH400 was more intended for the a BB becuse of the larger low end torque it puts out. ------------------ 71 basic C-10 350. The only option is the rust.No nothing on it, but thats all about to change. <A HREF="http://www.geocities.com/stevemau/slam33page.html?1004806705410 " TARGET=_blank>http://www.geocities.com/stevemau/slam33page.html?1004806705410 </A> __________________ 71 LWB 350/350still working on it but it's going tp be sweet. www.geocities.com/stevemau/slam33page.html " TARGET=_blank>http://www.geocities.com/stevemau/slam33page.html?1004806705410 </A>

05-06-2002, 11:11 AM	#4
fine69 Senior Member Join Date: Dec 1999 Location: Urbana,Ohio,USA Posts: 4,618	I hate to tell you this but, , Tons of these trucks were built with T400's behind smallblocks. I have owned several. Mostly 3/4 ton trucks. But i have seen 1/2 tons with the T400, and even a 1/2 ton 68 panel with a 327/T400 factory. I will take a T400 any day over a T350. I do tow alot though. __________________ 2008 Chevy HHR 1/2 panel. 1949 Chevy Panel truck(just sittin, waiting) Board member #6

05-06-2002, 11:53 AM	#5
COBALT Senior Member Join Date: Sep 2001 Location: Seattle, WA, USA Posts: 5,817	My '69 C20 came stock with a 350 4bolt main in front of a TH400. I simply love it. Strong and reliable. I like it so much in fact that I'm going to rebuild another TH400 and set up a work truck to have the same setup. One thing to consider is the availability of used TH400s. There's not a lot of Chevy cases left. Even if you prefer the TH350 its something to think about. ------------------ '69 3/4 ton C20 2wd w/ 350ci/400THM and a wood bed! '69 3/4 ton Custom 20 2wd w/ ORIGINAL 350ci/4sp Manual and a wood bed (parts beast). Seattle, WA. *See pics of my trucks and project at www.webshots.com! __________________ '69 3/4 ton C20 2wd-350ci/TH400 '69 3/4 ton Custom 20 2wd-350ci/4sp Manual '99 2wd 5.7 Chevy Tahoe Seattle, WA.

05-06-2002, 10:01 PM	#9
dmnall Registered User Join Date: Apr 2001 Location: Goleta, CA Posts: 505	Nothing wrong with either TH350 or TH400, just the fact that TH400 can take more abuse! If I could justify the cost, I would put a 4L80E tranny in my truck for Overdrive but the problem is this tranny requires a $ 2000 conversion kit to work with Older Trucks that did not have computers in them! Just realize when you do put a 700R4 in and you decide to tow with that tranny or even driving up a large Grade or Hill, Take it out of Overdrive, or you will see how weak a 700R4 will become!! I am currently running a TH400 and I plan to put in a Bowtie Overdrive 700R4 and I will be taking precautions when driving up Hills and Towing with it because I don't want a Dead Tranny on my hands !! This is just my opinion though !! ------------------ Truck #1 68 Chev LWB Fleet w/ Wood Floor (Sucks Gas and Hauls Ass!) and in process of Body Work... Truck #2 1994 GMC Sierra SL w/ 4.3L Vortec V6, 4L60E Auto!! __________________ 1968 C10 Truck LWB Fleetside 1968 C10 Truck SWB Stepside 1994 K2500 Ext Cab Fleetside 2008 Honda Civic Si lease

05-06-2002, 09:33 AM	#1
gmc-rob Registered User Join Date: Apr 2002 Location: Saskatoon,SK Canada Posts: 41	Transmissions Since all you guys seem to know so much about these trucks, what is the difference between a TH350 and TH400 and which on is more desirable. I know the 400 can take more torque than the 350 but which one would you rather have in your truck? Thanks Rob

05-06-2002, 10:10 AM	#2
tom hand CCRider Join Date: Feb 2000 Location: Olive Branch,MS,USA Posts: 2,232	I have always liked t-350's never had a problem with one. Unless you have a lot of money you can't build a smallblock stout enough to hurt one. If you are doing major towing or have a killer bigblock then it might be time to step up to a 400. Just keep in mind that a 400 uses more horsepower to do it's automatic thing, so you don't want to use one unless you have to. ------------------ 72 GMC Sierra SWB almost finished---- 84 Softail Olive Branch MS __________________ 72 GMC Sierra SWB almost finished---- 84 Softail Olive Branch MS

05-06-2002, 02:28 PM	#6
Fast68Chevy Account Suspended Join Date: May 2000 Location: IL Posts: 0	fine69, thats cuz 350 did not exist til 69,, only in maro in 68 was there th350 earlier than 69 [This message has been edited by Fast68Chevy (edited May 06, 2002).]

05-06-2002, 02:44 PM	#7
Woody Registered User Join Date: Feb 2000 Location: Georgetown, KY, USA Posts: 631	My truck still has the orginal T400 in it. It has not been rebuilt that I can tell. I have towed/hauled/hot rodded the hell out of it and it has almost 200k miles on it and still going.....it has been serviced (filter and fluid changed) a couple times. They are tough to beat. I hope to go to a 700R4 soon for gas milage... ------------------ Woody '69 Custom-10 Deluxe Short Fleetside,Factory 350cid/TH400,A/C,PS,PB,Carpet Coming soon 700R4, 350 Crate Engine, Pwr Disks...

05-06-2002, 07:22 PM	#8
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	I swear by the TH350. like said before...it'll take lots of money into your engie to kill a TH350. ------------------ '69 G.M.C. 350/350. Trying to clean up the left over damage from the Dope-Smokin-Old-Man I've been dubbed the Longhorn Freak/Fanatic/Expert, I just hope I can live up to it. FINALLY got the HORNIAC...a '70 one ton Longhorn with a Pontiac 350/350 and lots of 'personality'. Check out The Longhorn Webite. If you need a pic posted, E-mail me at longhornmail@yahoo.com Andy, in Columbus Ohio

05-06-2002, 10:08 PM	#10
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	If you want an indestructable overdrive, visit this site; http://www.gearvendors.com/commercial.html ------------------ '69 G.M.C. 350/350. Trying to clean up the left over damage from the Dope-Smokin-Old-Man I've been dubbed the Longhorn Freak/Fanatic/Expert, I just hope I can live up to it. FINALLY got the HORNIAC...a '70 one ton Longhorn with a Pontiac 350/350 and lots of 'personality'. Check out The Longhorn Webite. If you need a pic posted, E-mail me at longhornmail@yahoo.com My name is Andy...not Randy...I'm in Ohio...Not Illinois...close enough? Columbus Ohio



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