89 C 1500 with a 400 trans from factory??

[someotherguy]

TH400 (3L80) came in GMT400 2500 (8 lug, not 6) and 3500's 1988-1990 until the 4L80E was introduced in 1991.

However, some early 1500's got them, too. Not common at all but they do exist. I had a 1988 RCSB C1500 parts truck with the 3L80 and 4.3 V6, all original.

Richard

I knew I'd posted this pic here before. Plain Jane old truck though it did come with the quad lamp grille instead of the W/T style. Crank windows, vinyl floor.. blown head gasket 4.3 and 3L80. Still ran and yard-drove, just at the end of its life though.

Now that I look closer at the pic I realize p.o. must have swapped the GMC grille in. Wonder if he did the quad lamp setup at that time. Chevy emblems on the door molding. (by VIN it's a Chevy, 1GC first 3) too bad the SPID label was illegible, but all signs the 3L80 was original, down to the non-O/D shift indicator in the cluster.

Richard

 

[df2x4]

I seem to recall some 2500 Express Vans had a 4.3 Vortec + 4L80e, no?

Yup, pretty sure that's where Black Bear got the base tune for my truck when I did the 80E swap. I was just thinking about the trucks specifically when I made that comment earlier.

 

[Insert Quarter]

My '89 C2500 8 lug came with a 5.7L(4 bolt main), TH400/3L80, and a 9.5" semi-float

 

[C2500]

Hi. I have a stock 89 C 1500 5.7 that apparently was built with a TH 400 transmission instead of a 700R4. I thought all the trucks in this series came with the 700? Any info is appreciated. Thanks.

I have an 88 c2500/305 6 lug came with the 400

 

[TQS335]

I seem to recall some 2500 Express Vans had a 4.3 Vortec + 4L80e, no?

Thanks to all for the replies. This begs a question: How tough is it to swap out my 400 (3L80) for a 700R4 (4L80) so that I can have overdrive. Thanks

 

[PlayingWithTBI]

How tough is it to swap out my 400 (3L80) for a 700R4 (4L80) so that I can have overdrive.

The 700R4 is also called a 4L60 (not 80) so, you're getting a weaker trans.

 

[thegawd]

heres another option that you might not even be aware of.... leave your transmission right where it is and add a Gear Vender overdrive unit. it would make your 3L80 a 6 speed!

so you install this behind your transmission and have your driveshaft shortened.

Home - Gearvendors

RACING AND TOWING PERFORMANCEOVERDRIVE ECONOMY The Absolute Highest Horsepower Handling Overdrive you can buy! Gear-Splitting Performance and Overdrive Economy. For RV’s, Trucks, Muscle Cars, Hot Rods, and Racing. The Finest Quality Auxiliary Transmissions. The Ultimate in Horsepower Handling...

www.gearvendors.com

edit... there website is kind of old school, just like their company so your probably just going to have to give them a call.

I took a screenshot where they mention the TH400 in a trophy truck....

You must be registered for see images attach

 

[stutaeng]

Precision Transmission on YT gas done videos where they've mentioned the units are going to get GearVendors. I don't anything about them or own much they cost.

As far as 4L80e swap, you would have 3 options:

1. Use a PCM from '91-95 same truck as yours that came with the 4L80e. '91-'93 years would have to have transmission matched to the ECM. Those years had slightly different wiring and valve bodies internally.

2. Swap to a Vortec engine and electronics to control the transmission. Again, the transmission would have to be '94+.

3. Do a standalone transmission controller for the electronics

 

[Chuck_13]

My friend had a body shop in the late 80's early 90's and worked with him part time.One of the jobs I remember was an 89 C1500,plain as vanilla truck.RCSB,the only option was AC.Vinyl floor manual windows etc.The engine trans was a 4.3 and Turbo 400 (3L80 as I've just now learned).I was astounded that GM put a 400 behind the 4.3 but there it was.My friend and I were both driving mid 70's square bodies at the time,and he said if could have a new truck it would be just like the 89 we worked on.

 

[sweetk30]

I have parted 2 1985 square body c10 trucks with factory 4.3 4barrel qjet carb th400 deep pan combos .

What i dont get is why the extra 20+ hp loss of the th400 behind the already small hp of the 4.3 engine .

Always amazed me what the factory did .

I even parted a long bed truck with factory twin short bed fuel tanks .