Heat Tolerance of PET?

My latest AG batch that I mashed in the oven missed my target gravity by quite a bit. I know it was due to not using enough sparge water and not thinking all the way through how I was going to handle the larger grain bill for the batch. Now that I can look back at it, I think I can still mash in the large Megapot, then transfer the mash wort to an empty bucket, then use the pot again to sparge.

Question is, will PET tolerate a 155 or so temp?

How long? You should be OK.

Just long enough to empty the pot and put the sparge water in, maybe 2-3 minutes. Basically, I'll have 2 pots. 1 to mash (big) and the other one to heat the sparge water so it can be poured into the big pot after emptying the mash water into the PET bucket.

No problem.