Hey guys i,m looking to tackle this nasty 30 year old transmission leak this weekend, However i cant remember if this is a Borg Warner 12 or a GM 400 Can any of you tell by the horrible oil stained picture i took.. Thanks in advance. 1976

I,m thinking it is a Borg Warner 12 ( if i remember correctly ) Thanks

 

Looks BW12 to me, but its many years since I looked.

Is the vac modulator on the RH side of the casing, just above the gasket line, near the front = TH400

Vac modulator on the LH rear, on the reaa face = BW12.

XJS had TH400 , the earlier XJ12 had the BW12, but the crankshaft was different also on the V12, to take the converter snout, sooooooo, being a Chev, and maybe a 5/8 crank hole, a BW12 was used, as that converter has the snout to suit that hole. The TH400 snout was more a "dome" as apposed to a "shaft" style of teh BW12.

 

I will put it up the ramps and look under it, but it is being run by a chevy V-8 so it makes me lean towards the BW Thank you. I will let you know as soon as i get under it.

 

The BW12 pan gasket is almost square. The TH400 is very irregular.

As far as I know the XJS used the BW12 until May 1977 or thereabouts





Cheers
DD

 

You guys are the BEST! !!!!!!!