I've been bored and UTA has been making progress on the proposed 2024 budget and dropping some hints along the way.
As has been mentioned here before UTA, has received a federal grant to the tune of $60 Million to replace half of their original
SD Unit fleet. In their 2024 budget UTA is proposing $10 Million to the same SD Unit replacement.
Given the calculated cost of $3 Million per LRV the feds have calculated, the total amount of units initially funded for replacement is 23 (with UTA's $10mil). It's a pretty specific number. There are two generations of SD units in UTA's fleet: SD100 and SD160. Between the two there are 40 units: 23 SD100 and 17 SD160 units. The SD100s are between 3 and 5 years older, it makes sense that UTA is initially securing funding to replace them specifically. I'd bet they ask the legislature or apply for a grant to replace the remaining SD160 units before they take delivery of any new units. I'd hope that by the time an order is placed UTA orders additional units to support an Airport to UofU line.
I'm sure plenty of the people who view this thread already know the difference between an SD100 and SD160, but in case anyone here doesn't here is a photo comparison:
SD100: Has folding doors, some units have been repainted to match newer S70 units.
SD160: Pop out sliding doors, newer AC traction system.
These units still have plenty of life left in them, I wonder if they will be sold to Denver or Sacramento.
Other little notes from the budget:
UTA is planning to have Siemens repair 2 accident-damaged S70s. One of which was involved in a serious derailment in 2018 pictured below. (Photo: KSL)

Side note: To my knowledge the worst LRV repair UTA has had to have Siemens do at their factory was the vehicle involved in the 2016 North Temple derailment, that unit was remanufactured and put back in service on the S-line.
UTA is continuing the Frontrunner locomotive midlife overhaul. Once complete UTA locomotives will meet EPA Tier 1 or Tier 2 emissions standards. UTA's MP36 locomotives may only be 11-16 years old, but several components like the trucks and engine blocks are refurbished from much older locomotives.
UTA is anticipating delivery of the used Coaster BiLevel cars this year which will enable them to begin a midlife overhaul of their own BiLevel cars.
The UTA customer service center located in the old Rio Grande freight hub building at SL Central (not to be confused with the Passenger Depot, subject of the Rio Grande Plan) will be closing on October 2nd. Customer Service will now be located at UTA Meadowbrook. This is the last use of the building, Greyhound has already vacated and water has been shut off. The historic building will likely be torn down in the very immediate future.