Of the two types, I have found that one type (the good ones) are all steel and stay put and are hard to get on and off. When I bought my 300 td wagon last month it had only one hubcap. Owner said they just fell off. I bought some (and taped and painted them) after that I DIDN'T want to lose one. I found that that 3 of the ones I bought, and the remaining original one ('85) had a grey plastic fitting that contacts the inside of the wheel. They don't stay on. The old all metal ones fit into the caps I had and are a very tight fit......

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'85 300 TD wagon. Euro spec. 215,000 miles, real beater (for now). '59 f350 with cummins 6at, 54 gmc flatbed with cummins 6at, '92 f350 service truck with 7.3 NA IDI and 5 spd man tran, Grumman Aluminum stepvan with 6.2 (cabinet hauler) I like diesels.....