Transmission Shudder - Replace?

[shank0668]

2013 Yukon XL Denali 6L80 AWD.

Low rpm/lugging around 25mph I get a shudder. I noticed it and probably haven't put more than 20 miles on it since - it's been parked for weeks.

Yukon has 285,000 miles but runs and drives well and isn't rusty so I am considering fixing. I am unsure of the life it had previously but I put a new filter in it around 250k miles and dropped the pan and replaced fluid about 5000 miles ago. I am sure it is the torque converter like all 6L80's. I had a quote on a built trans and converter installed for $5,500 which is about all this is worth at this point...

What other options should I be considering - used for $1700ish, supposed refreshed with billet converter for $2,000ish?

 

[Joseph Garcia]

@NickTransmissions

 

[NickTransmissions]

2013 Yukon XL Denali 6L80 AWD.

Low rpm/lugging around 25mph I get a shudder. I noticed it and probably haven't put more than 20 miles on it since - it's been parked for weeks.

Yukon has 285,000 miles but runs and drives well and isn't rusty so I am considering fixing. I am unsure of the life it had previously but I put a new filter in it around 250k miles and dropped the pan and replaced fluid about 5000 miles ago. I am sure it is the torque converter like all 6L80's. I had a quote on a built trans and converter installed for $5,500 which is about all this is worth at this point...

What other options should I be considering - used for $1700ish, supposed refreshed with billet converter for $2,000ish?

At 285k, you have to assess the overall health of the vehicle and try your best to predict how many more miles of service life it has left. If the engine is still running strong and has good compression across all cylinders, leak down is within specified limits, no other major sub-system on it needs significant work then you may consider investing the $5500.00 in a proper overhaul to keep it on the road for another few years or so...The alternative is a new or certified used vehicle that will have a much longer service life (possibly only 20-30% of miles at most compared to your existing one) and possibly a powertrain warranty that covers you for at least the same amount of time you figure the 2013 Yukon will last.

So run all the numbers as well as take into account intangibles/stuff you can't quantify and see what direction looks best.

IMO, spending any money on anything other than a complete and proper overhaul is pissing money into the wind at this point, it's either all or nothing when it comes to the transmission. I offer 'refreshes' on numerous different transmissions that I build but the 6L family is not one of them. There's too many things that have to corrected, that if left out of the build profile, drastically increases the likelihood of a come back. A used unit is even riskier.