Vin Decode: Mack R

[cf685f]

Guys, I found an R model sitting out back of a barn. It appears to have been worked hard. It looks savable though. Hoods been killed. The owner cant tell me the year or any thing about the truck. Can anyone help me decode the vin:

R686ST18303

I guessing the 686 means a 300 mack with tip turbine....but does the ST tell me any more about the truck? I wasnt sure what all I can tell from the vin#.

Thanks for the information, I may make him an offer depending on what you guys tell me.

What does an r hood goes for?

[41chevy]

first 6 is the chassis GVW rating

86 is ENDT676 300 Maxidyne

T - Tractor

S - Six wheel chassis

[Green Dash]

Would all 686's have the tip turbine or did they still use the 86 designation for later 300 equipped R models with the charge air cooler?

[41chevy]

Would all 686's have the tip turbine or did they still use the 86 designation for later 300 equipped R models with the charge air cooler?

300 equipped according to my info no call out for CAC

[Superdog]

Would all 686's have the tip turbine or did they still use the 86 designation for later 300 equipped R models with the charge air cooler?

for a time they did,then they went to 88 for the Econodyne version and 90 for the Maxidyne version.

[thomastractorsvc]

The VIN number is before they changed to a 17 digit in I think around 82ish. my R was a 1980 R686ST66669 ordered in 12/12/1979 and final assembly build sheet signed 5/20/1980.

So based off the VIN/SN I would guess 1977 to 78. Take the number to the Mack dealer they should be able to look it up and tell you right away or send it to the Mack Museum and wait awhile.