When you say it has writing on it do you mean actual handwriting, written with a paint pen? If so, it is probably a junkyard tranny. In that case, I don't know what the 375 refers to. GM did make a THM375 - it was a light duty 400 with a different tailshaft and tailshaft housing designed to use a TH350 yoke. Externally it would appear identical to a 400, except the tailshaft housing will be marked "375-THM". Since these trannies were only used from 72 to 76, and then only in passenger cars, I find it extremely unlikely that you have one of those. Then there is the later THM375B, which is a HD TH350, and looks identical to a TH350. Since you said the pan looked like a 400, then it probably isn't one of these. Most likely it is a standard 400, although why they would put that behind a 4.3 is puzzling to me... Anyway, check the TS housing and count the number of splines on the output shaft. If you count 32 splines, then it is probably a 400.bronc3buster842001 said:
