2009 387 Peterbilt Motor mounts / ISX 871

[Nostalgic]

They don't look too bad. I'd change them when if/when you do the rear structure and/or clutch, but I don't think I'd tear into it just to replace the mounts.

[Evotrucker]

It's your truck end of the day, change them when you want or even if you want at all.

That certainly is a job!!! just for some rubber lol. if it were me and it wasnt bad then id just plan ahead for the job and anything else that you might as well replace while your at it when the tranny is down and out. that way you wont have any worries later on.