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18

I really think that it's more of a naming convention issue but there is a marked difference between 4x4 and AWD. In 4x4 all the wheels are "guaranteed" power. Power is sent from the engine to the transfer case and then the transfer case sends it to the front axle and rear axle. The reason I put guaranteed in quotes is because there is such a thing as full ...


11

Does anyone have a definitive answer as to which option I should choose? I do: you need matching tires. That said, it's your car and you have to make the decision. I'd tend to replace all four. @Paulster2 also makes a good point that you could shave down a new one to match. Let's start by looking at one of the most useful paragraphs from the Tire ...


11

My first thoughts, given the car is question, would be to check to see if there is a performance version of the car which features four wheel drive. For road use, if you have over 300bhp going through the front wheels, things can get difficult. A friend of mind had a 320bhp Seat Leon Cupra (Front wheel drive) and sold it to buy an Audi S3 (same basic ...


10

One of the things the other answers neglected to mention and is probably the key point between AWD and 4x4 is that AWD transfer cases will almost always be a single speed differential. The 4x4 will almost always have 4-wheel high and 4-wheel low ranges and be selectable. This provides more torque if the driver deems the situation to need it. 4x4 may also ...


8

They likely do hold some liability, since they should have known that an AWD should have matching tire diameters across all tires. They may argue that you hold some responsibility since the Impreza owners manual makes this pretty clear: . You must install four tires that are of the same size, circumference, construction, manufacturer, brand (tread ...


7

It says right on the webpage: Conventional all-wheel drive cars employ complex mechanical linkages to distribute power from a single engine to all four wheels. This sacrifices efficiency in favor of all weather traction. In contrast, each Model S motor is lighter, smaller and more efficient than its rear wheel drive counterpart, providing both improved ...


6

See Is it OK to replace only 2 tires on an AWD car?. If you call different Audi dealers you're likely to get differing answers regarding how much tread depth difference is OK for the all-wheel-drive system. Nonetheless, I would advocate calling to get specific recommendations for your vehicle, as some all-wheel drive systems are more sensitive to ...


6

First thing I'd check is that it's got the AWD driveline - there should be a driveshaft from the gearbox in the front connecting to a diff at the rear "axle", plus driveshafts from each rear wheel to the diff. If that's missing, well, there's your problem... Assuming it has an AWD driveline, my suspicion would be that the center diff that is supposed to ...


6

This is something I've commonly heard said, usually by tire salesmen, but I do not buy. The difference in speed of the rotating tires between 6/32" is very small and likely less than many other factors such as alignment and tire inflation differences. The differentials are meant to handle small differences between the different tires rotation speeds and ...


5

Before you start, I'd have a good read of the rules applying to it - I seem to remember that Germany is very strict on heavily modified cars, so you might well find there are restrictions on what you can do to it - modifying the monocoque (chassis/bodyshell) to allow the fitment of a propshaft and rear drive axle might well be restricted, or involve huge ...


4

Jerking and thumping when shifting through gears is an indication that you have bad either: bad engine mounts bad transmission mounts bad differential mounts bad axles a combination or all of the above Shifting into neutral does relieve the "tension", as you put it, but you need to care care of these issues. They can end up being costly.


4

4WD has the best traction in off road conditions, which is mainly what most larger vehicles are used for. As well as this, 4WD offers better fuel economy which is generally more favorable in a larger vehicle as these will already have a greater fuel consumption due to their added weight. You are correct about AWD being at least as good in conditions such as ...


4

Different outer tire diameters creates a different rate of rotation for each wheel. Depending on the design of the differential, maintaining higher speeds for a lengths of time with great enough differences in rotational speeds can create too much heat, which I imagine leads to break down of the lubrication and damage to the differential. It would be wise ...


3

This is pieced together from articles about this and the talk we had from a Tesla rep at the car leasing company I work for. The improved range of the dual motor setup arises from the front and rear gearboxes (one per motor, nothing interlinking them) having different ratios. Electric motors have a rpm range in which they operate most efficiently, having ...


3

"It depends"... I've historically opted to replace all 4 just to be safe (on my AWD with 3 LSD beast, on the RWD open diff I replace 1 at a time if needed :-) ). In theory a small difference won't blow up the transfer case or the diffs (there's always at least a TINY difference anyways). Normal wear with a normal rotation obviously doesn't violate the ...


3

I've heard it many times, but never seen any proof. See the question and my answer to this post. I have never read about it in any of the Factory Service Manuals I have been through, so I shelve it up as false. I think the idea is that new fluid, with all the fresh detergents, shock dirt and debris loose and cause problems. Again, never seen it happen.


3

It's unlikely that 2WD will save you a lot more fuel than AWD but it will save you more than zero. 2WD will definitely save you fuel over the 4WD Lock setting. The reality is that, no matter what setting you use, the engine still has to move the same mass of metal down the road. I.e., maximum efficiency is bounded. That said, in 2WD mode, you are avoiding ...


3

Short answer. Yes. Your vehicle could be pulling to the right for several reasons. It could be uneven tire wear (which would likely have been caused by an alignment issue), tire pressure (which you've checked), wheel damage (which you've checked) or misalignment. One thing you might try before going for an alignment is making sure that all four of your ...


3

It matters, but how much it matters varies from vehicle to vehicle. TireRack has an article about this topic -> Matching Tires on Four-Wheel Drive and All-Wheel Drive Vehicles Here is the Manufacture Specific info from the end of the article: Here are recommendations from some of the manufactures that Tire Rack currently serves for matching the tires ...


2

The general consensus on this is that it depends where you are intending to go - you want something that is common in the local area so that parts are readily available. The two standard choices are Land Rover (either Defender or Discovery) or Toyota (LandCruiser or Hilux) - Land Rovers tend to be more common in Africa, Toyotas are more common in Asia. Both ...


2

The first step is to pull the ABS codes. That will give us a starting point for trouble shooting. This model supports flash codes, you will need to jump across terminal A and H of the ALDL connector (under the drivers side of the dash). It may take about 30 seconds before the ABS light starts flashing codes. Count the flashes to get the code, they ...


2

Just as a note, awd systems I worked on in the past had a limit of 1 inch difference in circumference of any tire to avoid abnormal wear of the transfer case. And I did see several cases where the chain the case was already stretched with a bad jerking on take off, and new tires fixed the symptom although of course the underlying cause remained.


2

You can check the rear toe in exactly the same way you check the front toe -- using the same string setup, parallel to the car's centerline, measure the distance from the string to the leading and trailing edges of the wheel. One thing to be careful of is that the rear tread (a.k.a. track) may be different than the front. When you're lining up your string, ...


1

I am not an expert but I read in an article somewhere when Tesla introduced the P85D that the dual-motor version is more efficient at putting power to the wheels since it can use all four wheels instead of just the rear wheels. This even offsets the increased weight of the dual-motor setup and translates to a 2% increase in range.


1

You can get the CR-V, Pilot, Ridgeline, and Crosstour with the AWD option. Understand that these vehicles will not engage all four wheels at all times. If you are looking for a vehicle where all four wheels are engaged all of the time, I don't think you'll find one, whether it's a Honda or not. 4WD/AWD vehicles are designed with a bias built into the ...


1

I had the same issue. One tire needed to be replaced, tire store told me I had to replace all 4. Not wanting to give up good money for no reason, fearing they were just trying to get more money out of me, research led me to replace all 4 for better peace of mind and for a longer lasting Subaru. But the tire place did tell me if I purchased the insurance ...


1

FWIW, I've driven an AWD Volvo XC90 several times before and that was my experience as well. If that's normal, then it's the worst AWD system I've ever driven. Had terrible torque steer under hard acceleration, and front wheelspin was a major issue on loose surfaces. Didn't think much about it (even though it was new when I first drove it, and continued ...


1

Look, I agree with the tyre rack article to a certain extent. But let's all use a little common sense. Using their example (as I do) in rotating my full size spare on my Wrangler. Even when I swap out at every tyre rotation the act of not using 1 tyre for that set of 5000 miles creates a tyre circumference difference of about 1/8" of an inch. So by there ...



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