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**LEEVON** · 03-18-2013, 04:34 PM

Somebody asked a question about gearing and it got me thinking about my last '87. It was a swb 1/2 ton with 305TBI and what I believed to be factory 2.41 rear end behind a TH375 transmission. What the heck, you ask? Well, it's a TH400 with a TH350 output shaft. Odd duck to be sure! I actually really enjoyed driving it, and with the continually low RPM's around town and on the highway it was really quiet and smooth. It did get about the same mileage in town as on the highway which was a respectable 15mpg and I never had any problems until the transmission lost reverse. Seizing an opportunity I swapped in a 700R4 and 3:73 posi. I realized later I should have just left it alone and rebuilt the TH375 if for nothing else the novelty!

Has anybody had a truck with a similar transmission / gear combo? Was this even possible, or just a funny combo of replacement parts? Keith Seymore, what say you sir?

Here's the 'ole beast:

03-18-2013, 04:34 PM	#1
LEEVON Registered User Join Date: Jul 2006 Location: Ozark, MO Posts: 4,887	1/2 ton factory 2.41 gears! Somebody asked a question about gearing and it got me thinking about my last '87. It was a swb 1/2 ton with 305TBI and what I believed to be factory 2.41 rear end behind a TH375 transmission. What the heck, you ask? Well, it's a TH400 with a TH350 output shaft. Odd duck to be sure! I actually really enjoyed driving it, and with the continually low RPM's around town and on the highway it was really quiet and smooth. It did get about the same mileage in town as on the highway which was a respectable 15mpg and I never had any problems until the transmission lost reverse. Seizing an opportunity I swapped in a 700R4 and 3:73 posi. I realized later I should have just left it alone and rebuilt the TH375 if for nothing else the novelty! Has anybody had a truck with a similar transmission / gear combo? Was this even possible, or just a funny combo of replacement parts? Keith Seymore, what say you sir? Here's the 'ole beast: Attached Images __________________ '20 Silverado Trail Boss ~ '17 Tahoe ~ '79 K15 Sierra Grande ~ '76 Blazer 2wd ~ '71 Cheyenne swb ~ '55 Pontiac Safari ~'50 3100 bagged ~ '80 Wife ~ Late model kids