LsSwapDaWorld

I don’t think there stock gears because when I went to go get tuned my tuner was saying my cluster rpm’s weren’t reading right unless that’s a cluster problem not sure

Truck is a 06 says it on title but how can I find out what gears it has ?

I’ve got this 06 Chevy Silverado single cab I bought it was a v6 to v8 swap I’m looking to find out if my differential was swapped the truck currently has caliper breaks in the back and I’ve seen a couple people mention they have drums on there 06 what could I do to find out if my differential was swapped ?