Oil recommendations and a few questions

[Warrantw5]

Hey guys.  Looking for oil recommendations for a 73 Challenger with a 416 stroker engine.  It has solid lifters.  The guy I bought it from used Mobil 1 15w50.  I thought I would need zddp.  Would Amsoil Z-rod 15w50 be better?

The car has Auburn Pro Series rear diff with Richmond 3.91 gears.  Recommendations on differential fluid would be appreciated.

Also, dash lights don't work. I will test for power this weekend, but I suspect it is the dimmer. Any idea where to buy a dimmer switch.

The inside of the car is outrageously loud at any speed.  I would appreciate any recommendations on sound dampening.

Thanks for the help. Jeff

[moreparts]

Hello Jeff, I'm a flat tappet kind of guy, but I'm fairly sure your solid lifter engine doesn't need any zinc supplements.  That's supposedly one of the many joys of the solid lifters.  Re the dash lights, that dimmer switch is a good bet.  You may look at taking it apart yourself to see what the problem is or using a service.  I think someone on here rebuilds them or you may score a deal on eBay if you get real lucky.  But definitely check your wiring first.  Check the bulbs too.  Sometimes one out can cause issues with the string.

[Chryco Psycho]

Jim @ JS Restorations for the switch rebuild .
Flat tappet cams all need Zinc additive , the best oils are Joe Gibbs or Brad Penn , I like 10-40w but it depends on the clearances machined into your engine . If you can find SJ OR SL rated oils they are good for flat tappets , often off road / agriculture oils are still rated for SJ or SL . You can also run any oil + additive but it is harder to know how much ZDDP you end up with .
I have heard of issues with synthetic oils in diffs , I use 80-90w Castrol , or 75-90 if you want to risk syn oil .
There are a number of products similar to Dynamat or you can install rubber under the carpets as the factory did , there is also Lizard skin a ceramic foam that work well but is tough to apply , best done with spray equipment .

[Warrantw5]

Thanks guys.  I am researching the dynamat. That seems to be good stuff.  I will post on how it works.

[dodj]

IMO, jumper the dimmer switch. The dash lights are pretty poor in an E body, nobody 'dims' them.

[Northcuda]

I use Australian Penrite oil in my 416. With over 2200 ppm levels, it's one of the richest oils in zinc.
https://www.penriteoil.com.au/products/10-tenths-racing-15w-50-100-pao-ester

[Warrantw5]

Thanks for the help.  Just got the dash lights working.  Tested the fuse and removed all the bulbs except the shifter light.  Put it back together and they work.  Nice and bright.  The dimmer certainly has a sweet spot.

[76orangewagon]

You really should check out BND automotive, he specially formulates oils for your application. I use all his products in my cars.
http://www.bndautomotive.com/