I think you meant ’ front '.
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I know my 05 Odyssey specifies 2 or 3 PSI higher in the back than the front, but that’s due to the increased cargo load in the rear, not the high performance scenarios brought by the others 
Different front and rear tire sizes are handling and horsepower related. Wheel widths, too. A current Mustang model has the same tire size front and rear but the rear wheels are 1/2 inch wider. Handling, just handling.
One FWD Pontiac model, with a V8, even had smaller rear tires.
Larger rear tires are also a styling thing. It looks good. The last 3 generations of Corvettes even have 1 inch larger diameter wheels as well as wider. As @texases points out, there is more room for bigger in the rear as they don’t steer.
“Simple answers” are often not complete. First, Mercedes doesn’t “design tires” in a vacuum. So called “Mercedes Original” tires are developed in cooperation with companies that actually make tires, based on the performance parameters they want to achieve. Second, the rear tires are still bearing less weight, although the size of the tires may well go a long way toward explaining things. Third, since you provided minimal information about your vehicle beyond “2010 Mercedes Benz E Class,” I had no way to know whether it had different size front and rear tires. For example, the 2010 2wd E350 comes with either 245/45 17’s front and rear or 245/40 18’s in front and 265/35 18’s in the rear. Your specific vehicle–which you still haven’t identified–could have had either or even something completely different. Which prompted my whole question.
My guess would be, relatively “skinny” tires are easier to turn left to right while wide tires have better traction. The extra room in the wheel well is another factor.
Yes they are, but with power steering it really doesn’t matter anymore.
Great breakdown. Thanks.
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It might still have an effect on handling with the front tires functioning like skate blades. I really couldn’t say.
Actually, the opposite is true, with narrower, higher profile tires:
They want to track straight, and resist steering input, while wider, lower profiles respond quicker to steering input. Narrow tires also have stronger self-aligning torque compared to that of wider tires. That, along with alignment angles such as Caster, contribute to the heaviness you feel when you start to turn the steering wheel to one side or the other.
Wider tires are also subject more to something called ‘tramlining’, since there is more tire to either side of the tire centerline, and to either side of the steering axis. Tramlining is the tendency for a tire to follow ruts and other road imperfections.
Engineers know this, so that’s why, on some cars, they specify either lower cold tire pressures in the front, or, a higher profile, narrower wheel and tire size up front. This provides straightline stability during the high-power takeoffs some high performance vehicles are capable of.
I’ve been told that ambulances have tracking problems in the snow with the dual wheels in the back. So both the front and the back have to clear snow.
I would think that would apply to any vehicle with that drive configuration. Lots of pickups with duals in the rear.
Many years ago, I rode in the ambulance with a friend who was having a heart attack, and this was in the immediate aftermath of a really big snow/ice storm. Shortly after I got into the cab with the driver, he said, “I just want you to know that I have almost no control of this thing, so please be sure that you’re belted-in very tightly”. At that point, they almost had two passengers with cardiac problems.
Occasionally I drove an ambulance, but they were the old 3/4 ton vans without duals. One was giving to us by NASA, we were hauling supplies, not patient. Wanted to get back before our coworkers went home, told my boss I was going to hit the lights and siren to get back sooner, like cops do on the way to a donut shop. NASA had disconnected the lights&siren!
The only ambulance I ever rode in was an old something like a 52 Pontiac conversion. Nice ride but a little cramped. Navy gray.
If that is a Morris Mini Cooper, the transmission is right under the crankshaft.
Edit: sorry bout that, I didn’t notice that this is an old post.
Well I don’t even remember that. I had been following a guy from New Zealand that was restoring an old Morris minor. Then the virus hit and he stopped working and never saw if he ever got it done or not. Stripped everything down to bare bones but seemed to have no problem getting parts from the uk.
The Morris Mini Cooper, Austin Healy 1100 and MG-GT all shared the same engine/transmission configuration where the transmission was built into the crankcase. They share the same oil. The Mini-Cooper S had a DOHC, 4 valve per cylinder option that produced around 100HP which in a car that light, made it blazingly fast. I believe that version was made by Cosworth. The Austin America was similar except it had a semi-automatic transmission and Air Ride suspension.
The suspension was actually hydraulic. There would have been no way to incorporate the complexities of an air suspension system into a really cheap car like that model.
I actually test drove one of those Austin America’s. The “hydrolastic” suspension did have to be charged with air as hydraulic fluid is not “lastic” Anyway I was used to 0-60 in 8 seconds or less and I did not like it. But they did claim 40 mpg IIRC.
“If your tyre pressure is correct but the tyre pressure warning remains on, the TPMS may need to be reset. To do so, turn on the ignition, then press the left or right steering wheel button to access the Service menu, and then press the “OK” button. Navigate through the service menu until the “Tire Pressure” option is highlighted (read this guide Mercedes e350 Tire Pressure [Recommended] - Nerdy Car also). When you press “OK,” the pressure in each tyre should be displayed. Press the down button until the display prompts you to use the current tyre pressures as a reference. When you press “OK” one more time, you will be notified that the TPMS has been restarted.”