I got owned. It's not a TH400 . Diff between TH350 vs. TH375

[73c20jim]

Just going to old lady drive it. I have both transmissions. Which would be better. Remember casual driving, probably with a camper on the back.

P.S. Not like "The little old lady from Pasadena."

 

[78C10BigTen]

Have a feeing if your yanking a camper most will say 400. My truck is a 350 and i crank on it pretty hard but never tow. I personally dont like 3 speed autos, i wish i had OD.

 

[Shorty81]

I was always partial to the good ole 400. Strong tranny.

 

[73c20jim]

Further examination shows it is a TH375. What is better TH350 or TH375???

 

[yevgenievich]

Sell both and buy a th400

 

[Snoots]

Neva hoid of a th375.

Go with the 400. They suck more hp but are stronger for the camper.

 

[73c20jim]

I don't have a TH400. I have a TH375. So it's either the 350 or the 375.

No other choices.


Thanks.

 

[foamypirate]

TH375 is just a TH400 with a TH350 27-spline output...

 

[73c20jim]

Actually the internals are different. Lite duty version of TH400. But is it better than a TH350???

 

[foamypirate]

I don't think the internals are different enough than a standard TH400 to make it weaker than a TH350. Output shaft, and likely fewer clutches in each pack. I'd run it over the TH350 if towing, but you honestly probably wouldn't go wrong with either one.

 

[Matt69olds]

If it’s a 375 trans (based on a 400 case) it will have thicker pistons in each clutch pack that hold fewer clutches, and the smaller output shaft. You can easily install earlier pistons and up the clutch count and swap the output shaft. Other than those changes, they are identical.

There is also a 375B trans that is based on the 350 case. It’s a heavy duty 350 with additional clutches.


There is also a th475 trans, it’s a heavy duty trans with straight cut gears. I have found them in RVs, box trucks, and other heavy vehicles. Sometimes the will have a cable operated parking brake on the output shaft and extension housing. They aren’t really any stronger, the straight cut gears help prevent wear from the the helical gears tending to push rearward under constant heavy loads. They are also louder, same as the old Muncie rock crusher trans. Those gears are cut at a more shallow angle than the standard Muncie, also to prevent wear from heavy loads. The straight cut/shallow helical cut gears are much more noisy.

Ok, trans is class 101 is dismissed.

 

[75gmck25]

Just for a point of comparison, my '75 K25 Camper Special (8400 GVW) came from the factory with a TH350, so GM thought they were good enough to handle the camper. IIRC, I think my max camper weight is about 2650 lbs, according to the data plate on the truck.

Bruce

 

[Rusty Nail]

I vote th-350 almost every time.

I sucks half as much horsepower as a th-400 and provides for better fuel mileage.

I understand this is "run what ya brung"... 375/400 whatever!

The last opportunity I had to pick 350 or 400 I chose 350 for the above listed reasons. I STILL haven't been sorry about that choice, 18 years later.
I have since bought a 400 though for two main reasons;

A) I've never owned a vehicle that had one in it.
B) I want to.

Hope this helps! :flag:

 

[idahovette]

Just for a point of comparison, my '75 K25 Camper Special (8400 GVW) came from the factory with a TH350, so GM thought they were good enough to handle the camper. IIRC, I think my max camper weight is about 2650 lbs, according to the data plate on the truck.

Bruce

Sounds just like my 75 K20 Chevrolet 350 ,350 ,203, 4.10 gears. Used it with a 9 1/2 ' self-contained Kit brand camper for a lot of years ,a lot of miles, and LOTS of gas! Went to California , lots of trips to Oregon coast and many trips to Seattle to watch Baseball games, even a trip back to New York City, camper on it downtown Manhattan. People saw the Idaho plates, the gun rack and they got out of the way. This was in October 1976.

 

[75gmck25]

Your '75 K20 sounds identical to my '75 K25. I'm still using mine for various personal construction jobs, and some days it gets a work out.

I had them load up 2 cubic yards of topsoil without stopping to figure out that it probably weighed at least 3500 lbs. I heard creaks and groans out of the suspension that I had never heard before, but everything worked fine.

To the OP - when you equip your truck for a heavy camper, make sure you also buy the right tires. Load Range E or 10 ply rating truck tires are what you need, since LT tires usually do not have a high enough load rating. The 10 ply tires are readily available in 245/R75-16 and and other sizes, and usually not much more expensive than the LT tires.

Bruce