I believe they have different rear end ratios. I know the 87 has a 2.65. The 86 probably 2.88. If you crawl under the car and look at the back of the differential you will find out. Sometimes you have to do some scrubbing. I also believe the 86 may not have had the trap oxidizer. I have known of some that never came with it but I am sure it is possible that some have.

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-disav

99 E300 TURBODIESEL Astral Silver 282K - AMG brakes, suspension, monoblocks, speedo & interior - Full Load Maxed on IP by custom Speed Tuning USA Chip - T3/T4 Garrett - EGR/MAF delete
98 E300 TURBODIESEL Alexandrite Green on black leather 289K
95 E300 DIESEL Green Queen 267K SOLD
84 300D 216k SOLD
87 300D 299K #22 head - intercooler - full load adj. - 8sec 0-60mph - SOLD
76 300D 214K SOLD