ordered a Cofle cable from Autohausaz (22.99 with shipping) and promptly broke it
got a Motormite cable from advanceautoparts (23.84 with tax) and got it installed right

aside from my mistake in installing the Cofle cable it appears that the manner in which the speedo end of the cable is attached could be better
a soft base metal attachment is clamped onto the end of the cofle cable and then sheathed fine enough but does not come with lubricant the instructions recommend using

the motormite cable came with lubricant and the speedo end of the cable is itself squared off and has a brass fitting threaded onto it which keeps it from recessing into the sheath


Procedure:
from inside vehicle:
remove light switch knob and trim plates on either side of central instrument cluster
unscrew 2 medium phillips screws from each side of instrument cluster
unscrew 2 screws from top of steering shaft cover
pop cover from steering wheel and use 27mm deep-well socket to remove steering wheel (be sure to mark alignment)
slide inst cluster towards you a few inches and notice large black cable coming from center of speedo region and continuing forward to firewall
unscrew 1/2 turn the knob which encircles the cable and holds it onto the speedo (both 240s ive owned had broken knobs - so yours may be missing as well)

from engine compartment identify speedo cable thus:
from passenger side of transmission the speedo cable comes forward into engine bay and travels upward against backside of firewall passing through one clips which holds cable against backwall, cable then turns towards driverside, remains against firewall and is retained with a clip against firewall directly behind valvecover, the cable then passes through the firewall below the main wiring harness in its own hole with fitted seal

pull speedo cable through firewall from engine compartment
unhook cable from clip behind valve cover leave clip in place
unscrew retainer clip held in place with phillips screw low on firewall passenger side remove clip from cable

jack up car and get under passenger side follow cable from engine bay as it hugs the interior edge of central frame and is held in place with another retainer clip and then enters rear of transmission

remove last retainer clip with 8mm wrench and unscrew cable retaining nut from speedo gear housing
note: there may or may not be a second clip holding cable retension nut against transmission housing with an allen nut, if so, you must also remove allen nut
but, this is also a good time to replace the o-ring inside speed gear housing, so you may as well remove the allen nut, pull out the small yellowed-plastic housing and replace the oring. be careful not to lose the small dogear which holds speedo gear housing in transmission
reassemble gear housing and dog ear

acquire new cable and remove cable from sheath so it may be lubricated then return cable to sheath

ALWAYS make sure cable is never kinked or bent
feed 18-24" of cable back through firewall and into passenger compartment
i found the route a little more straight routed over the vent hoses and then into back of speedo
pull cable inner part out a few inches and slip into back of speedo until it is seated then slide sheath down and secure knob with a half turn
ease cluster back into dash and pull slack cable into engine compartment
make sure cable is not kinked or bent
on transmission end of cable you can test for smooth operation by spinning cable inner one way or the other and seeing if speedo needle moves
route cable along firewall through retainer clips and under car along frame
but wait to secure the 8mm bolt retainer until completely done
check at each direction change along the way to make sure speedo cable rotates freely and moves speedo needle

crawl back under car and gingerly bend speedo cable to allow entrance into speedo gear
using a pair of needle nose pliers i was able to get the cable inner to rotate enough to allow it to enter the small square gear shaft, then seat the sheath and secure gnurled nut
attach cable to underside frame rail with remaining 8mm bolt and clip
clean oil from hands and reassemble interior panels
Enjoy a non-shuddering speedometer needle, tighter cruise control and odometer numbers that get bigger assuring your position in the volvo driver's hall of fame



what did i do wrong the first time?
I attached it at the transmission end and forced it into speedo cluster end, causing cable to bind at speedo attachment point and break before i had driven 5 feet.

By attaching at the speedo end first we can check for binds and kinks and also rotate cable for entry into final hole. Attaching at tranny end will be a cumbersome sucess.
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