▁engine ▁( 2 4 ▁stud ) ▁and ▁g ear box ▁ ▁No . ▁ 3 ▁- ▁Ford ▁Canada ▁V 8 ▁engine ▁( 2 4 ▁stud ) ▁and ▁g ear box ▁ ▁The ▁two ▁marks ▁were : ▁ ▁Mark ▁I ▁- ▁B end ix ▁bra ke ▁system ▁ ▁Mark ▁II ▁- ▁Gir ling ▁bra ke ▁system ▁ ▁R oles ▁ ▁There ▁were ▁not ▁many ▁differences ▁between ▁variants , ▁mainly ▁se ating ▁and ▁arm our ▁plate ▁location : ▁ ▁Track ed ▁Person nel ▁Car rier ▁( TP C ) ▁E qui pped ▁with ▁a ▁front ▁ben ch ▁seat ▁and ▁se ating ▁for ▁troops ▁on ▁the ▁track ▁gu ards . ▁Front al ▁and ▁full ▁side ▁arm our ▁fitted . ▁ ▁Track ed ▁Tow ing ▁( TT ) ▁- ▁Initial ly ▁known ▁as ▁' T ractor ▁Anti - t ank , ▁M k I ' ▁E qui pped ▁with ▁four ▁single ▁seats ▁and ▁am mun ition ▁st ow age ▁on ▁the ▁track ▁gu ards . ▁U sed ▁for ▁to wing ▁the ▁ 4 . 2 ▁in ch ▁mort ar ▁and ▁ha uling ▁the ▁Q F ▁ 2 ▁p ound er ▁and ▁Q F ▁ 6 ▁p ound er ▁anti - t ank ▁guns ▁and ▁carrying ▁its ▁crew . ▁Front al ▁and ▁front ▁quarter ▁arm our ▁fitted . ▁The ▁main ▁variant ▁by ▁number ▁manufact ured . ▁ ▁Track ed ▁C able ▁L ayer ▁Mechan ical ▁( T CL M ) ▁A ▁vehicle ▁for ▁Royal ▁Corps ▁of ▁Sign als ▁work . ▁No ▁arm our ▁fitted . ▁ ▁Track ed