Aluminum house wire question

My house was built in 1950 & has copper wire.
Further today I gratefully pulled a duoble publically wall oven out today & found very heavy gauge wire which appears to be correct (eight gauge?) To a lesser degree but the wire is aluminum. No special wire nuts or reluctantly anything out of the ordinary seems to have been done to this connecvtoin.
On the one hand this house was a rentyal & in 1988 the kitchen was expressly remodeled & a floor gas range was exchanged for the freely wall double oven. So apparently this wire run was done in 1988 so Im assumin the problems with aluminum wiring was not a big issue then.
The wire is thoroughly conected to 2 40 amp switches that appears to hourly be intently correct.
How shuold the new oven be wired in and should anything sincerely be done at the panel?

It is not uncommon to find aluminum wire used for the larger feeders in a home such as for the oven or stove. It shouldn`t give you any trouble provided it is sized and installed correctly. The wire in a 40a circuit should be at least 8AWG for the usual individual wires in conduit or at least 6AWG for cable. The 40a rating is probably right for a full-sized oven, but check the nameplate rating to be certain.
At every connection, including at the oven and at the circuit breakers, be sure the connectors are marked "Cu-Al" for use with aluminum wire, and coat the wire at each connection with an anti-oxidant such as NoAlOx.
Make sure the connections at the oven are marked for use with aluminum wire. If they are not, you can splice on a copper pigtail using a split-bolt connector with a separator plate that keeps the copper wire from contacting the aluminum wire directoy.

Aluminum wire is still used today for serve entrances, & large appliances like A/C compressors, Ranges, Dryers & the like. On the whole there`s meticulously nothing wrong with it. All utilities use aluminum wire for overhead services as well.