How can I remove the old gear shift knob and install a new one in my 2000 SLS Cadilac

The OP Adds

Unfortunately the type of knob has no clips , screws etc. The new replacement knob has the shift release (the trigger you squeeze to change gears) pushed in at the top with the spring not engaged which I am pretty sure has something to do with the old ones removal, ie I think I have to push the top of the trigger part in to release the knob, but I am not game to do it until I am sure that's what is required. I have scoured the internet but can only find American instructional videos which are different to the Australian setup. Thanks Greg"

There is some help here Greg plus there are a couple of links to Australian Colorado forums where you would get an Aussie perspective and perhaps a service manual.

https://www.google.com/search?q=2015+Holden+RG+Colorado+Automatic+Australia+remove+automatic+gear+shift+knob

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If you have a stick shift ( floor shift) remove the boot around the gear stick and the insulation on the floor to reveal the 4 bolts that hold the shift turret on to the top of the box. Undo the bolts and lift the gear lever assembly out of the gear box.

Most gear shift knobs are just screwed on. Try turning it anti clockwise if yu can not see any screw holding it

i have a 1994 cadillac seville sls and it wont shift out of 2nd gear i have replaced the shift silenoid "B" and the vss and it still wont shift and the pcm is still good. What else could it be?

there is a Cclip type snap ring almost at the base of the handle remove it them pull the knob up watch for the spring

Good day
No the steering wheel don't need to be remove.
1. remove the instrument panel cluster opening finish panel assembly. remove the 3 screws that retains the upper steering column shroud and remove cover.
2. insert a scratch awl into the access hole on lower steering column shroud and push in the ignition lock cylinder release pin. insert the ignition key into the lock, turn ignition to run position and remove the lock cylinder from the steering column. remove lower steering column shroud. unsnap and slide gearshift lever boot up toward end of gearshift lever.

NOTE: ALWAYS INSTALL NEW GEARSHIFT LEVER RETAINING PIN DURING REASSEMBLY

3. remove gearshift lever retaining pin by lightly tapping with a drift punch and hammer. disconnect gearshift lever harness connector. remove gearshift lever. to install reverse removal procedure.

hope this helps

Cheers

On my 2000 jetta glx, I had to replace both the shift knob and boot as one. It is built as one unit. You have to pull the boot up over the shift knob, break/bend a clip to "unlock" the shift knob then pull up. I hope the new knob you got has the boot built in and comes with a new clip.

There are two types of shift knobs. One that unscrews and one that the lower trim of the shift knob separates from the knob using a trim stick. After separating the lower trim from the knob pull upward to release the knob from the shift lever. If a new shifter assembly is being installed, unscrew the original shift knob or separate the lower trim from the knob and pull up to remove the knob from the shift lever. Screw the knob onto the new shifter assembly's lever no more than 14 turns or install the lower trim onto the shift lever then push the knob onto the shift lever and install the lower trim piece onto the shift knob.