Ok to Use Synthec?

[siamanis]

A friend of mine has a 1978 Trans Am. Is it ok to use a synthetic in an older engine? I did some searching, yet could not find anything specific. I guess Amsoil, Redline, German Castrol, ect. would be good recommendations?

Thanks for the help.

 

[simple_gifts]

Several people have noticed RL does not do well in older, traditional design (GM) motors. If the car sits a lot and isn't "built", RL would be a waste. I seem to recall 1978 isn't one of the "horsepower years" for GM.

 

[siamanis]

I assume by "RL" you mean Redline? Just making sure. Ok, how about using synthetic in general. That should be fine, right?

 

[Johnny]

How many miles on this car? Do you know if he has had the engine down for rebuild. If it does not leak out, it will do no harm. A high mileage car that old could leak through the seals after the synthetic cleans it out. Probably got some hard seals under the gunk that's covering them up.

 

[Amkeer]

I would stick with 20w50 Havoline or Castrol GTX.

 

[tdi-rick]

I used to run Mobil 1 5w-50 exclusively in the 351 Clevland in my old '80 F100(F150 in NA), after we re-built it in '93.

 

[Gotrek]

I run mobil 1 in my 1980 chrysler with a 360 without any issues.

I however just switched to Tech 2000 (walmarts supertech in the US) for cost reasons (20$ vs 35$ for a 4.4L jug)