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Tranmission
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Picture of ryegal
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Hi Can anyone tell me what size transmission my 1975 class C has? Thanks


Proud owner of a 1975 classic class C
 
Posts: 108 | Location: Seattle,wa,usa | Member Since: 12-31-2004Reply With QuoteReport This Post
Supporting Member of Barthmobile.com 12/12
Picture of Lee
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I'm gonna guess a THM-350, maybe 375, but a quick look at the pan shape should tell you....FMI:

http://www.nastyz28.com/chevy-...n-identification.php
 
Posts: 1403 | Location: Frederick, Maryland | Member Since: 09-12-2003Reply With QuoteReport This Post
Supporting Member of Barthmobile.com 2/16
Captain Doom
Picture of Rusty
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I'd bet a THM-400 - they were pretty much standard on the cutaway vans of that vintage.


Rusty


MilSpec AMG 6.5L TD 230HP; built-to-order by Peninsular Engines:  Hi-pop injectors, gear-driven camshaft, non-waste-gated, high-output turbo, 18:1 pistons.  Fuel economy increased by 15-20%, power, WOW!"StaRV II"

'94 28' Breakaway: MilSpec AMG 6.5L TD 230HP

Nelson and Chester, not-spoiled Golden Retrievers

Sometimes I think we're alone in the universe, and sometimes I think we're not.
In either case the idea is quite staggering.
- Arthur C. Clarke

It was a woman who drove me to drink, and I've been searching thirty years to find her and thank her - W. C. Fields
 
Posts: 8201 | Location: Brooker, FL, USA | Member Since: 09-08-2005Reply With QuoteReport This Post
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Supporting Member of Barthmobile.com 11/13
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Some small block vans came with a TH350. TH400 was an extra cost option. The pan shape will tell you, for sure.

The TH400 is tougher, but TH350 has lower 1st and 2nd gear, better suited to a small block with a load, and still plenty tough.

If you have a 350, use the lever to shift down to 2nd instead of mashing the throttle. That gas pedal kickdown is a heck of a jolt on a 350. On the TH400, 2nd is closer to high, so the jolt isn't as hard on things.


.

84 30T PeeThirty-Something, 502 powered
 
Posts: 7397 | Location: AZ Central Highlands | Member Since: 01-09-2001Reply With QuoteReport This Post
Supporting Member of Barthmobile.com 7/17
Picture of Doorman
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75 G30 came with TH400s.


1986 31' Regal -1976 Class C
454/T400 P30 -350/T400 G30
twin cntr beds - 21' rear bath
 
Posts: 779 | Location: Dayton, Ohio | Member Since: 09-27-2009Reply With QuoteReport This Post
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Supporting Member of Barthmobile.com 11/13
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From the GM Motor Home Chassis Service Guide (Red):

"Chevrolet motor homes are equipped with one of two different automatic transmissions, the 350C (G-Series) and the 400-475 (P-Series). Both are fully automatic units which use a three-element hydraulic torque converter."


.

84 30T PeeThirty-Something, 502 powered
 
Posts: 7397 | Location: AZ Central Highlands | Member Since: 01-09-2001Reply With QuoteReport This Post
Supporting Member of Barthmobile.com 7/17
Picture of Doorman
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My 76 G30 has a th400 as did my 75 Class C.


1986 31' Regal -1976 Class C
454/T400 P30 -350/T400 G30
twin cntr beds - 21' rear bath
 
Posts: 779 | Location: Dayton, Ohio | Member Since: 09-27-2009Reply With QuoteReport This Post
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Picture of Steve VW
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Try this thread;

http://www.barthmobile.com/eve...943946077#5943946077

Pictures and discussion of the THM400 and trans coolers. mechanic


8607-3346-33TFPOB------9708-M0037-37MM-01
86 Regal SE 33 Tag axle--"98" Monarch 37
Chev P3(7) 454TBI--------Cummins 8.3 300 hp
400 hp fuel injected-------6 spd Allison, Spartan MM
 
Posts: 3231 | Location: Kalkaska, MI | Member Since: 02-04-2011Reply With QuoteReport This Post
Supporting Member of Barthmobile.com 5/16
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Does anyone know what the max temperatures for a TH475 transmission is? Keep hearing conflicting numbers from other sites......?

Thanks~
 
Posts: 81 | Location: IN | Member Since: 09-30-2015Reply With QuoteReport This Post
Supporting Member of Barthmobile.com 2/16
Captain Doom
Picture of Rusty
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Here.

Optimum operating temps are 185°-205°F. Synthetics slightly raise ATF temperature tolerance, but the clutch faces still can fail with excessive temps.


Rusty


MilSpec AMG 6.5L TD 230HP; built-to-order by Peninsular Engines:  Hi-pop injectors, gear-driven camshaft, non-waste-gated, high-output turbo, 18:1 pistons.  Fuel economy increased by 15-20%, power, WOW!"StaRV II"

'94 28' Breakaway: MilSpec AMG 6.5L TD 230HP

Nelson and Chester, not-spoiled Golden Retrievers

Sometimes I think we're alone in the universe, and sometimes I think we're not.
In either case the idea is quite staggering.
- Arthur C. Clarke

It was a woman who drove me to drink, and I've been searching thirty years to find her and thank her - W. C. Fields
 
Posts: 8201 | Location: Brooker, FL, USA | Member Since: 09-08-2005Reply With QuoteReport This Post
Supporting Member of Barthmobile.com 5/16
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Thank you, Rusty.
 
Posts: 81 | Location: IN | Member Since: 09-30-2015Reply With QuoteReport This Post
Supporting Member of Barthmobile.com 7/17
Picture of Steve VW
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Depending on the location of the trans temp sender you may get way different values.

I had the sender in the (hot) line out to the cooler, often saw 300 degrees on long hills. I found this alarming. (Not sure why they put it there) When I put the sender in the trans pan I see about 160 to 180.

I have one Hayden cooler in the trans loop. I had two but temps were too low. I do not use the cooler in the radiator.

The hot line to the cooler runs hotter but by the time the fluid returns to the pan it is at normal temp. The fluid will oxidize more quickly at the higher temps but the short duration limits the damage. Meanwhile the internal trans temps are normal, so things are good for seals and clutches.

http://www.barthmobile.com/eve...1087061/m/5943946077


8607-3346-33TFPOB------9708-M0037-37MM-01
86 Regal SE 33 Tag axle--"98" Monarch 37
Chev P3(7) 454TBI--------Cummins 8.3 300 hp
400 hp fuel injected-------6 spd Allison, Spartan MM
 
Posts: 3231 | Location: Kalkaska, MI | Member Since: 02-04-2011Reply With QuoteReport This Post
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