well im new to the truck world, i just got a 04 sierra. It was originally a
4.3 and the previous owner did a 4.8 swap. The problem im having is my oil pressure gauge and temp are not working, Now i know all about the motors in the gauges going bad, but my buddy just got his whole cluster rebuild in his 03 Silverado and we try it on mine and still the same thing. i did check to make sure the oil sending unit n temp sensor are plug in, what else could i check? also the truck has a th350 swap if that would affect things. Thanks for the help

 

200 views and no response?? come on guys

 

You can't reliably swap clusters between vehicles from 03-onwards. Must reprogram them for the VIN else odd things break. If you don't have a check engine light or a code for the coolant sensor performance, the issue is with your cluster or wiring at the cluster.

Seeing as the original vehicle had a V6, I bet the owner did NOT add/move wires as needed in the harness for the cluster to function properly. It's not a straight swap for the engine or engine harness to cluster.

Why exactly someone would do a TH350 in behind a 4.8 baffles me, unless they just didn't have anything else laying around and had no plans to drive it on the interstate.

 

thanks for the help, I think the guy was going for a turbo track truck, I think your rite doh it might be some wires they dint wire up rite, but were should I check??

 

It's not simple or fast. You need a v8 BCM and v8 interior harness. The instrument cluster is largely driven from the BCM in the 03+ trucks. There is a writeup or two around here and as I recall it wasn't worth the effort involved. Much faster to get custom instrumentation and feed it data directly.

 

can you use a v6 bcm with a v8?? and the v6 engine harness?? truck looks to already have a v8 bcm and harness, it looks to be wired rite, or are they both pretty much the same??

 

They're different, particularly with the oil pressure, coolant temperature and tach signal. You would need to get wiring diagrams for the two models and compare them though.

 

hmmm, going to have to take a look at it, everything works but the oil n temp gauge, I know there plug up rite so idk