Need some help please read
 

Hey everyone I need to know how serious this is. I'm hoping I can get it fixed tomorow but I somehow bought 80w 140 instad of 75w90 for the differential. I've put like 400 miles , is it gonna ruin anything if I get it changed tomorrow? Like have I already done serious damage?

if you haven't heard any strange noises coming from your cars rearend,you should be ok.i would change it asap

I feel like a total doof , I mustve been looking at the right stuff and looked away and therm grabbd the wrong stuff without noticing. I hope I can get it done tomorrow. I'm picking it up from the tint place tomorrow and the shop I go to is in the same town

The more viscous lube will probably reduce gas mileage VERY slightly and reduce gear noise. It will be fine.

So basically change it asap but it should be ok since I haven't driven that much with the wrong fluid?

should be fine