Factory Transmission? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

HotRod73 · 03-12-2007, 11:54 PM

What did a factory 87 swb 4.3 liter tbi v6 come with for a tranny? i know some where standard and some were automatics... but mine was swapped from a 4.3 to a 305 tbi and i noticed i have a th400 transmission... did they come with these or was this added when they put in the 305 motor? arent th400s stronger than th350s??

Pyrotechnic · 03-13-2007, 01:22 AM

A 4.3 would most likely have come with a Turbo 350 or a 700R4. Same for the 305. Turbo 400's usually came with big blocks.

MylilBowTie · 03-13-2007, 02:10 AM

87 Was the odd year that I've seen alot of th375s. It looks like a th400 but it has a longer tailshaft and smaller size output shaft of a th350/700r4. I've got two of them one was a 5.0 and the other 4.3. Some also have HD cast into the bellhousing. Not to be confused for a th475 with strait cut planetary gears.

HotRod73 · 03-13-2007, 11:49 AM

so it could be a turbo 375? it has the same pan style?

MylilBowTie · 03-13-2007, 05:33 PM

Same pan style as a th400 or th350? Where is the modulator valve located on it? Is it on the passenger side or on the rear by the tailshaft housing?

If you could post a picture of it that would be alot easier to id (not absolutely necessary though).

HotRod73 · 03-13-2007, 11:20 PM

th400 style pan

bigtruck81 · 03-14-2007, 12:03 AM

the TH350 was killed off in 86, so no chance of a TH350 (actually a TH350C after 81). i've seen 700s behind 4.3s, as well as the TH375 and the TH400.

MylilBowTie · 03-14-2007, 01:02 AM

The th350c was made after 81, my 84 had one. The book I have covers the th350c from 1979-1984. I'm sure a few more have went out the door after 84 also. Though the greater major started shifting to the 700r4 by then.

HotRod73 · 03-14-2007, 11:25 AM

so th375 and th400 have the same style pan?? are they stronger than a th350?

MylilBowTie · 03-14-2007, 04:26 PM

The pans are the same but a few parts are different. Yes it is rated higher and can hold more power than th350. Its like how they "detune" engines in a way. They are still pretty good but don't have the heavier duty parts that the short tail th400s have.

There should be an id tag on your transmission. Should be on the passenger side. Look for a sheet metal tag that has Letters and numbers. If you can get those I can lookup the id for it.

lurch115 · 03-14-2007, 10:21 PM

i bought an '87 350 tbi truck last summer that has a 400th in it...thought it was kinda odd to see it in that new of a truck...but it is a true 400th

bigtruck81 · 03-14-2007, 10:22 PM

Quote:

Originally Posted by lurch115

i bought an '87 350 tbi truck last summer that has a 400th in it...thought it was kinda odd to see it in that new of a truck...but it is a true 400th

TH400s were available until at least 1991 when they were replaced by the 4L80E

03-12-2007, 11:54 PM	#1
HotRod73 Registered User Join Date: Mar 2006 Location: Norman, Oklahoma Posts: 553	Factory Transmission? What did a factory 87 swb 4.3 liter tbi v6 come with for a tranny? i know some where standard and some were automatics... but mine was swapped from a 4.3 to a 305 tbi and i noticed i have a th400 transmission... did they come with these or was this added when they put in the 305 motor? arent th400s stronger than th350s?? __________________ 1973 Chevrolet C20 (Under Construction)

03-13-2007, 01:22 AM	#2
Pyrotechnic Registered User Join Date: Feb 2007 Location: Austin, TX Posts: 3,930	Re: Factory Transmission? A 4.3 would most likely have come with a Turbo 350 or a 700R4. Same for the 305. Turbo 400's usually came with big blocks.

03-13-2007, 02:10 AM	#3
MylilBowTie Right turn Clyde Join Date: Nov 2002 Location: Cincinnati, Ohio Posts: 2,911	Re: Factory Transmission? 87 Was the odd year that I've seen alot of th375s. It looks like a th400 but it has a longer tailshaft and smaller size output shaft of a th350/700r4. I've got two of them one was a 5.0 and the other 4.3. Some also have HD cast into the bellhousing. Not to be confused for a th475 with strait cut planetary gears. __________________ 1974 C25 LWB: 454 4bbl Carb / TH400 / 3.73 1992 Camaro RS 305 TBI

03-13-2007, 11:49 AM	#4
HotRod73 Registered User Join Date: Mar 2006 Location: Norman, Oklahoma Posts: 553	Re: Factory Transmission? so it could be a turbo 375? it has the same pan style? __________________ 1973 Chevrolet C20 (Under Construction)

03-13-2007, 05:33 PM	#5
MylilBowTie Right turn Clyde Join Date: Nov 2002 Location: Cincinnati, Ohio Posts: 2,911	Re: Factory Transmission? Same pan style as a th400 or th350? Where is the modulator valve located on it? Is it on the passenger side or on the rear by the tailshaft housing? If you could post a picture of it that would be alot easier to id (not absolutely necessary though). __________________ 1974 C25 LWB: 454 4bbl Carb / TH400 / 3.73 1992 Camaro RS 305 TBI

03-13-2007, 11:20 PM	#6
HotRod73 Registered User Join Date: Mar 2006 Location: Norman, Oklahoma Posts: 553	Re: Factory Transmission? th400 style pan __________________ 1973 Chevrolet C20 (Under Construction)

03-14-2007, 12:03 AM	#7
bigtruck81 Registered User Join Date: Feb 2004 Location: northern, in Posts: 350	Re: Factory Transmission? the TH350 was killed off in 86, so no chance of a TH350 (actually a TH350C after 81). i've seen 700s behind 4.3s, as well as the TH375 and the TH400.

03-14-2007, 01:02 AM	#8
MylilBowTie Right turn Clyde Join Date: Nov 2002 Location: Cincinnati, Ohio Posts: 2,911	Re: Factory Transmission? The th350c was made after 81, my 84 had one. The book I have covers the th350c from 1979-1984. I'm sure a few more have went out the door after 84 also. Though the greater major started shifting to the 700r4 by then. __________________ 1974 C25 LWB: 454 4bbl Carb / TH400 / 3.73 1992 Camaro RS 305 TBI

03-14-2007, 11:25 AM	#9
HotRod73 Registered User Join Date: Mar 2006 Location: Norman, Oklahoma Posts: 553	Re: Factory Transmission? so th375 and th400 have the same style pan?? are they stronger than a th350? __________________ 1973 Chevrolet C20 (Under Construction)

03-14-2007, 04:26 PM	#10
MylilBowTie Right turn Clyde Join Date: Nov 2002 Location: Cincinnati, Ohio Posts: 2,911	Re: Factory Transmission? The pans are the same but a few parts are different. Yes it is rated higher and can hold more power than th350. Its like how they "detune" engines in a way. They are still pretty good but don't have the heavier duty parts that the short tail th400s have. There should be an id tag on your transmission. Should be on the passenger side. Look for a sheet metal tag that has Letters and numbers. If you can get those I can lookup the id for it. __________________ 1974 C25 LWB: 454 4bbl Carb / TH400 / 3.73 1992 Camaro RS 305 TBI

03-14-2007, 10:21 PM	#11
lurch115 Registered User Join Date: Oct 2006 Location: iowa Posts: 722	Re: Factory Transmission? i bought an '87 350 tbi truck last summer that has a 400th in it...thought it was kinda odd to see it in that new of a truck...but it is a true 400th __________________ "Horsepower is how fast you hit the wall, torque is how far you carry the wall with you." '84 chevy half ton short box 2wd, 67,000 actual miles '03 chevy 1500 HD crew cab 4x4 standard box, 6.0L



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