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The crush zone of SUV’s and other large cars are larger, but in general, the increase is not a large as the increase in mass. The energy to be absorbed in a crash is directly proportional to the mass of the car. A small car has all of the room in front to accommodate the engine and transmission, accessory drive, radiator and fans. The much heavier SUV does not (usually) have an increased crush distance between the driver and the front bumper that is proportional to the increased mass. Some may, and you can judge the overall crash effectiveness by looking at the NHTSA frontal crash scores. The IIHS can be a useful source of crash effectiveness, but I don’t trust them as much, because they are working for the insurance industry and do not always follow rigorous testing methodology.
It depends on the kind of crash. For a car-to-car crash, the larger and heavier car is generally safer because the car larger car experiences lower peak decelleration. In car-to-barrier crashes, the lighter car generally is safer because the ratio of crush zone to vehicle mass is better. A typical 4000 pound car does not have 33% greater crush zone depth than a 3000 lb car, yet it has to absorb 33% more energy in the crash. Also, all other things being equal, lighter cars corner and brake better than heavy cars, so they are more likely to avoid a crash, which is the safest outcome. you can also judge car crash safety by looking up their government crash ratings at the NHTSA site. You will see that crash safety scores are not always proportional to vehicle size.
My experience is that they review any year-to-year changes with the appropriate engineers, but the manuals are written by a publication department. Maybe the first manual was written by the engineers!
First check the steering column; particularly find where the u-joint is (it is under the dash) and inspect it. it can either wear-out or the bolts that tighten it to the steering shaft could have loosened. If you only feel the free-play when the engine is on, then the likely problem is the connection from the electric power steering motor (I assume your car has electric PS) to the steering column. On most cars their is a plastic or rubber gear that transmits torque from the electric motor to the steering column or steering rack. This “gear” can wear out. With the engine off, try to observe or feel if there is any overall free-play in the system. You can do this by placing one hand on the front tire while wiggling the steering wheel (you might need an assistant). If there is no overall free-play and you still have the feel of free-play when the car is on, it is probably the PS motor gear. Finally, it is possible that your steering rack is worn out, but this will show in the overall free-play when the car is off.
1) I would buy a flood damaged car before I would be a crash-repaired on. The 2 problems with flood-damaged cars are mildew in the carpets and upholstery, and electrical problems due to water. The first one is east to assess, mostly based on smell. The electrical system of modern cars is pretty waterproof, so if the car has had enough time to dry-out and everything electrical and electronic works properly (no engine codes), there should be no future failures due to the water.
2) I know how difficult it is to bleed the Prius brakes. If you do not have the Toyota diagnostics hookup to open the valves that allow bleeding, there is a work-around. Look it up on PriusChat. You could also purchase an OBD2 diagnostic tool with TechStream. TechStream software should allow proper brake bleeding. 10-year old brake fluid will come out brown.
A car that has been in an accident may have repaired well-enough to look undamaged, but hidden damage to the underlying unibody, like wrinkled or bent structural parts, will not be as strong as they were originally. More importantly, the car may be more subject to corrosion because the repair parts are likely not as well-protected as the factory parts. Factory body and chassis parts may be zinc coated and /or phosphated before painting. The other thing to consider is that the suspension geometry might be altered in a crash and, therefore the car may be difficult to align after a crash. It is difficult to know how much value a car loses from being in an accident and then repaired.
Old brake fluid doesn’t wear-out the brake system it causes corrosion throughout the system. The corrosion can lead to leaking seals and frozen pistons in the calipers. Replacing the calipers will be expensive (parts +labor).
In rough order of importance to me:
1) look for signs of accident repair by looking for wrinkles in the unibody. Look carefully around the radiator mounts, in the engine compartment, the floor of the trunk, and get underneath
2) See the service history of the car. If the car has less than 100 k miles, it probably has only needed regular oil and filter changes. Make sure this maintenance was don on-schedule and with the proper oil. If the owner only use synthetic oil, that is a plus. If the car has over 100,000 miles there is a lot of extra maintenance and service required. Look at the maintenance section of the owner’s manual and find out if everything on it was done
3) If brake fluid has not been flushed at least every 4 years, that is big minus.
4) If the owner used a remote starter to warm it up on cold mornings, I would not buy the car
5) Remove the oil fill cap and look for signs of sludge. Sludge is an indication of a lot of short trips or insufficient maintenance
6) The engine should start, run and idle smoothly and the only sound you should be able to hear at idle is the fuel injectors. Listen both after a cold-start and after a drive.
7) Garage-kept is a major plus
8) another check for any major accident damage is to either follow the car in your car while it is driven and look for dog-tracking (the front wheels not following the rear), and any signs of blue or black smoke from the tailpipeGood Luck!
Very important. Too much torque and you can break or crack the fastener or the suspension component. Too little and the joint will not be clamped up sufficiently to resist all of the loading, or the bolt or nut may loosen up eventually from vibrations. Either way, the consequences can be a sudden failure while driving. A typical suspension fastener is there to provide enough clamping force to a joint so that the joint can not separate or slide. Please don’t try to do suspension work on a car without the torque specs and a good torque wrench. You will see what I mean when you see all of the torque specs in the shop manual, and see that almost every joint has different specs.
Dave
You should be able to buy all of the suspension bolts at the car dealership parts department. If you want to try to buy generic bolts that will work, you will need to measure the dimensions of the bolts (length, diameter and thread pitch) and try to find matching ones on-line or in a hardware store. For all modern cars these are metric measurements. Note that many OEM bolts have built-in washers and the ones you find from fastener stores will not, so you will need to find appropriate washers for under the bolt heads. Finally, you will need to match the grade of the bolt. Every fastener should have a number stamped on the head (like 8.8). This is the grade indicating how strong the bolt material is. You need to match this. In a pinch you should be alright exceeding the grade (like use a 9.8 in place of an 8.8), but that is not ideal because the higher strength bolts are also more brittle and may load up the joint a bit differently for the same torque spec.
And please do not even start the job until you have a torque wrench and the torque specs from the shop manual.
No definitely not! Any substance on the threads of bolts drastically changes the amount of load (stretch) you will get from a given amount of torque. You will over-stress the bolts if you torque them up and the threads are not clean and dry. If you don’t over-stress the fasteners, there is a chance that bolt or nut will oosen in-service due to vibrations. You are using a torque wrench set to the proper torque for each suspension fastener?
The only proper and safe way to install critical fasteners, like suspension bolts and nuts, is with a torque wrench set properly. The torque specs can be found in the shop manual for your car, and is probably accessible online. Fastener torque is designed to provide a certain clamping force without over-stressing the fastener or part and preventing the parts from loosening due to vibrations.
The answer is generally no, you don’t have to get an alignment because you have probably not had to remove any of the adjustable pieces. There are some tolerances to consider, for instance if you had to disconnect the big bolts attaching the strut to the hub, the slop in the bolt-to-hub interface could allow up to about 1/4 degree of camber change, depending on how you put it back together. If you are fussy about alignment settings you could have that checked, but if your camber on one side is off enough to matter, you will notice the car pulling to one side or the other.
Toyota/Lexus ball joints tend to last a very long time, so if you only had to replace it because it ripped, you do not have to replace the other side.
If you have a limited slip differential between the front and rear axles, it will always be slipping and wear-out quickly. Some newer vehicles with electronically controlled couplings between the front and rear will not be able to control properly (and their clutches will wear-out or overheat) if the 2 axles are always rotating at different speeds
If you have a limited slip differential between the front and rear axles, it will always be slipping and wear-out quickly. Some newer vehicles with electronically controlled couplings between the front and rear will not be able to control properly (and their clutches will wear-out or overheat) if the 2 axles are always rotating at different speeds
