Having lived eaten and breathed used cars for coming on 30 years, I have gotten a little smarter. I never buy a used car more than 12 years old (1993 model) because thats when the rubber on the bushings, brake calipers and shocks and even trim and various other places needs to be replaced, particularly calipers and bushings.
Why that is, I don't know. Obviously it stresses out.Its funny but I know there have been some incredible innovations in suspensions and engines and the automotive industry lately.
I just wonder if manufacturers are proposing changes to rubber, ie rubber/polymer combinations or other materials that will have an enhanced life so that cars would last longer.

Bushings and other suspension pieces are easy to replace. In fact, that's one of the best things you can do to restore a new car feel to an old car. I am in the middle of replacing all the bushings and ball joints on my 1985 300D. I am hoping to have it on the road this weekend.

I think that car manuf's are not in the buisness of making cars last longer...

But in other markets, Industrial equipment (?), machine tools (?), hydraulic hoses etc, perhaps we will start seeing rubber there lasting longer.

-John

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2009 Kia Sedona
2009 Honda Odyssey EX-L
12006 Jetta Pumpe Duse
(insert Mercedes here)

Husband, Father, sometimes friend =)

Hondas and Toyotas have the polymer stuff and it does last but i can't take the hard stiff ride.

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1993 Mercedes Benz 300D 2.5 205K (ex wife's)
1984 Mercedes Benz 300SD 320K (SOLD)
2004 Mercedes Benz C240 75K
1995 GMC Sierra 2WD 5.7L 188K
1983 Mercedes Benz 300SD 239K (SOLD)
1987 BMW 325i 220K (SOLD FOR SALVAGE)

609 Certification

several 82 and 83 benzes that still have most of the original hoses, brake hoses, and many other rubber parts.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

so you would rather buy a car on the verge of having its rubber trim/bushings fail than to buy one that has already had this work done?

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http://i68.photobucket.com/albums/i1...Untitled-1.jpg

10-20 years for most rubber parts.

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1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

I work with engineers whose job is to specify elastomer (rubber) components for automotive use. They have wonderful materials available for design, but as John said, no more quality is designed into the part than is necessary, and only enough quality is added to take away business from another manufacturer. After all, the manufacturers are really getting squeezed by costs.

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95 E320 Cabriolet, 159K

so you would rather buy a car on the verge of having its rubber trim/bushings fail than to buy one that has already had this work done?

On my 87 300D I spent quite some time rebuilding the front end rubber, and I did all the work myself. It was terrible, because I did it last summer when the heat was bad, like now. I ended up doing a lot of restoration to this car, but i sold it because, I just wasnt "me", it was a big Luxury Mercedes, looked like the paint was brand new, and I like "beaters", cars you can park in the City or anywhere and not worry about someone coming out and scratching your paint......

Temporarily I am driving a 95 SAAB beater until I get my 85 300D back on the road. I didnt have to do a thing to this car; I 'm guessing the rubber would be good until 2008, but that doesnt matter to me, because soon as my 85 300D is back to spec, I'm selling the Saab.

Why do tires look beat after 2 years?
Why can't they make a special gloss coating on the outside wall and bind it to the tire, or else why cant they make a longer lasting Tire Gloss coating..I dont think either of these things are impossible.
I know it sounds dumb and stupid and vain, but nothing makes a car look worse then when the tires arent dressed right. My daughter is driving a 88 Corolla with the ugliest looking black steel rims since the Model T and one day I spray painted them silver as a joke.
When i was done I was shocked!!! The car actually looked brand new....

This is merely anecdotal... but I think rubber used to last much longer than it now does. My case: One Pirelli tire. CN70 Cinturato whitewall radial. Sized, IIRC, in the old FR70-14 format. Made in Argentina or Brazil. Easily older than the 1981 300SD which brought it into my life. (it just has that early 1970s look. Can't explain it any better than that.) Car came on three peeling chrome Bundt wheels with chain store cheap 205-70-14 tires, and one silver Bundt with this prehistoric Pirelli. I bought the car from my boss, and I always said, prior to purchase, that getting rid of that ancient tire was priority 1 once purchased... but no time, and a hectic schedule of travel intervened.

I drove it on 2000 miles of highway roadtrips around AZ and CA in summer heat. Later, Replaced the rims with 420 SEL equipment... that Pirelli still looks better, cracks-wise, than any of the other 7 tires which I have for the car. Strange.

How did the car feel afterward, I'm thinking of doing the same thing to my 87 300d and would love to have that solid, nothing shakes feel of a new car. The w124 was probably the stiffes car of its era-I know the 126 folks will dispute this- when measured from a chassis frequency standpoint, GM even used it as a target for when they developed the Olds Aurora chassis. In any case what I'm trying to say is that with all new rubber and joints and an already stiff chassis then you can get that new car feel.

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87 300d Turbo 241K with original #14 head (blue)
87 300d Turbo 198K will run great again someday (silver)
84 300sd sold ( buyer drove it to Paraguay )

I replace both sets of bushings on the control arms. The new part for the rear bushing added a lot of Beef to the rear bushing.
I also replaced the eccentric bolts
I also replace (yikess) the Bilsteins and ball joints.
I redid the calipers

The reason i say Yikes, is I still remember doing all that work in the Heat and how long it took me to do it, and the car is already sold less than 365 days later. It really rode smoothly and I used to cruise down the NJ Turnpike at 100 mph effortlessly at 4 am on my 100 mile drive to work.

That is one hell of car. But it was 20 years old and needed a lot of upkeep, because I also had to fix the AC, timing belt, electric vacuum pump, blower fan, and I said thats it when i read that the Head could fail. It just seemed like a BIG car and a LUXURY car. It got a lot of attention and I didnt like that, I'm low key.

Nothing lasts forever, MB does seem to use better rubber parts then most other car makes though.

Life span of the rubber also depends on what life it lived, a garaged New England car that is driven on the weekends can have 20 year old door seals that are still pretty good. Now take that same car that has sat outside in TX all its life and the rubber is rock hard.

Also you need to keep the rubber parts protected, protectants like 303 work great and keep rubber parts looking like new. My tires are over a year old and still look like new.

But no matter what you do if you have old cars you will have to replace rubber parts at some point. Thats just the way it is, the only way to avoid it is drive new cars.

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1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200