Quick U-Joint question

[AustinBelair]

Quick question. My 87 has the TH375 transmission and I want to order new u-joints. I looked on Rockauto and all they specify is 1 or 2 piece driveshaft. Nothing about the transmission used. Does anyone know what U-joint I need at the trans? I would assume a TH350 since the TH375 uses the TH350 long tailshaft

[kwmech]

Odd transmission for an 87 year model. Measure the width across the cap and then across from cap to cap

[cadillac_al]

I'll bet it still takes the same ujoint as a th350. I still don't really believe that th375's were used in Chevy trucks.

[sweetk30]

always best to measure cap size and cross width to verify .

best on the market these days the 4x4 guys love is spicer life series non greaseable .

[kwmech]

Originally Posted by cadillac_al

I'll bet it still takes the same ujoint as a th350. I still don't really believe that th375's were used in Chevy trucks.

They weren't, he probably has a 700 unless that was swapped in at some point in its life

[AustinBelair]

It is a TH375

TH400 case with a long TH350 tailshaft

[cadillac_al]

Looks like a long tail th400 to me. The th375 had the smaller 27 spline th350 yoke.

[kwmech]

Originally Posted by AustinBelair

It is a TH375

TH400 case with a long TH350 tailshaft

Nice, a whole lot stronger than a 700. No OD though

[Desert1957]

Originally Posted by cadillac_al

Looks like a long tail th400 to me. The th375 had the smaller 27 spline th350 yoke.

If its the original transmission its a 375, My 87 heavy half has one with a two piece drive shaft.

Here is a quote from this link.
http://wildaboutcarsonline.com/cgi-b...=9950419968967

"The TH 375, is simply a TH 400 with a long output shaft that mates to the smaller TH 350 drive shaft yoke. This can be identified by "375-THM" cast into the tail housing. Internally the clutch packs originally had fewer friction plates. The 375 rating was a result of the smaller yoke and fewer clutch friction plates.

To confuse the matter, some heavy duty TH 350s were also designated THM375-B. The key to telling the difference is the shape of the pan. "

[AustinBelair]

Originally Posted by Desert1957

If its the original transmission its a 375, My 87 heavy half has one with a two piece drive shaft.

Here is a quote from this link.
http://wildaboutcarsonline.com/cgi-b...=9950419968967

"The TH 375, is simply a TH 400 with a long output shaft that mates to the smaller TH 350 drive shaft yoke. This can be identified by "375-THM" cast into the tail housing. Internally the clutch packs originally had fewer friction plates. The 375 rating was a result of the smaller yoke and fewer clutch friction plates.

To confuse the matter, some heavy duty TH 350s were also designated THM375-B. The key to telling the difference is the shape of the pan. "

Haha yep and mine has the long tailshaft BUT does not have the 375-THM on the bottom so I am guessing it's a newer unit without the casting.