Does anyone know if I can install rear disc brakes either through modification on the rear axel of my 1987 420 SEL or swap the axel (like older mustangs did with lincoln rear ends to get disc brakes)? I just want to improve my braking, especially when trying to slow down from 115+ mph on the freeway.

87 420 SEL 191,000 mi

Doesn't it already have disc brakes in the rear?

Your car should already have disc brakes all around. To improve braking performance:

1) Bleed the brakes with a pressure bleeder (like Speedi-Bleed, etc) using 25-30psi, and use ATE SuperBlue or Type 200 Gold fluid. (Valvolne SynPower fluid is a cheaper alternative.)

2) Buy Porterfield R4-S carbon-Kevlar brake pads front & rear. They are NOT cheap but the performance is astounding. They take a long time to bed in, so go easy on them for 3-500 miles before you attempt any hard stops.

If you need to do REPEATED stops from 100mph+, then it's time to look into larger brakes front & rear. I know what works on 124/201 chassis, but I know very little about the 126 brake fitments, so I can't recommend anything there - sorry. I bet the Porterfield pads will do the trick.

Good luck!

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Dave
Boise, ID
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