Rebuilding transmission at 850k miles, preventive plus or potential waste of $?

Yeah I'm thinking that putting a completely different tranny in would be way too expensive and cumbersome. Probably all kinds of other parts to change, plus ecm reprogramming or replacing, who knows. I was quoted $3600 parts and labor for drop, rebuild, reinstall + $750 for a brand new clutch. I'll just start with having them inspect everything they can without dropping it, then go from there.

 

Thank you, I'll bet the shop I've had in mind this whole time has a dyno. They are drivetrain specialists, Eaton Fuller authorized rebuilds, etc..

 

Turns out my leveling valve was bad...again. Big bad vibrations in 8th are gone, no more rattling from the bell housing either. But uphill or in major wind fully loaded she just feels like she's about to give up...so #### loud, I can feel the stress she is taking, losing power. Just feels like she is about to die on me any time now. All I need is her toholdTutogether one more year! Hehe...

 

EGR #2 gave a high voltage code this week....the above symptoms I have mentioned are included in the diagnosis of EGR failure...I asked them to look at the injector cups while in there..(I know they are not related but I figured I would ask...as long as she is in the shop...right?) Even the service manager thought that was a waste...shocked the hell out of me, this shop is usually trying to get every penny possible out of o/o's. $1293 EGR #2 r&r... liking my local Volvo shop a bit more lately

 

Just an update, egr #2 replaced. Mileage still crap, but that is my fault. However I do think I have regained some, not much, but some power. Was thinking of blow-by, seeing as how the unit has almost 850k on her now. But a laboratory oil analysis showed not only is she all good, but lowwww normal readings! NO fuel in the oil, nothing abnormal, not even close, at a 25,200k PM.

Not my usual interval, but I would rather go over by 1k or so to get her home to my regular place. All drivetrain fluids were good, clean, and full... Aside from the transmission, it's not losing any fluid, just burning it up they say.

So, now my question still is, how can I get some of her old power back? Only a 12 liter I know, but I gotta believe there is more there. I know she has gone downhill since I bought her at 594k. I am still considering proactively rebuilding the transmission. What about exhaust? I know nothing about diesels when it comes to that. Does the stack get clogged up like a catalytic converter on a 4 wheeler with high mileage and choke it? Any other advice friends?