Britprius

As John above says the evidence is not anecdotal. Tyre pressures also have a big bearing on fuel consumption. Higher pressures in the same tyres bring a saving in fuel used. This is at the expense of ride comfort, and possibly road grip. Using the higher of the settings of those on the door jam label is probably the sensible pressure to use for economy. There are other factors affecting fuel consumption such as wheel alignment, and sticking brakes "particularly sticking slide pins". Warm weather also improves fuel consumption. On the Prius there was as much as a 10mpg improvement from winter to summer. Some of this is put down to the engine needing to run to provide cabin heat. John.

Very interesting write up with much useful information. Something you may or may not know. The "Curt" tow bar is not legal to use in the UK/Europe as it has not been type tested. It can be used for bike carriers or cargo boxes, but cannot be used to pull a trailer no matter how small. What you use it for is totally up to you, but there are insurance implications as I found out the hard way. All tow bars fitted now have to be type approved, and be marked with the appropriate numbers unless for some strange reason it is fitted to a commercial vehicle. John.

Good find on the spacers. I see fitting a spacer at the top of the cone as the best option without any reliability problems. The lower fixing brackets could be modified in a number of ways, but I see they supply extension brackets in the kit anyway. A 20mm thick spacer would raise the car about 30mm. This would be ideal in your situation, but another idea would be to buy the 30mm version,and cut them through at 20mm as both pieces could be fitted if you needed more height or 10mm pieces if you need less. Effectively giving three height options at only £5 more. John

The system with monitors in each wheel although not always utilised actually transmits more information than is usually displayed. The system not only transmits the real pressure "not just a low set pressure" it also sends a different code for each wheel, the tyre temperature, and the level of charge of the batteries for each sensor. John.

I had a Prius on which the CT was based. The larger wheels with low profile tyres dropped the mpg by around 5 against using the smaller 205/55/16 wheels and tyres. I found that over 130,000 miles the best tyres for fuel economy, road holding, quite running, and ware life were Hankook. "I cannot remember the type name but it had green in it" The next best tyres were Goodyear performance efficiency tyres, but these only lasted 18,000 miles against the Hankook 34,000 miles The worst tyres on the car were the OEM Bridgestone Ecopia that were not fuel efficient, and got noisier as they worn to the point I thought I had faulty wheel bearings, but it was the tyres. I got rid of them at 15,000 miles. John.

Aldi are doing Bosch wiper blades of all sizes up to 30 inches at £4-99 each. John.

The spring cone looks like this. As you can see at the bottom it has a circular flange of 120mm dia that the spring along with the mounting rubber sits on centred by the tube of 84 mm dia. The spacer will sit on here. A similar tube will need to protrude from the spacer to centre the spring. This could be an extension of the existing tube made from sheet steel. If fitting a spacer at the top of the cone. See pictures A ring will be required with an ID of 66mm, and an OD of 95mm. This will need to be drilled on a PCD of 46 mm, but the holes are not equidistant. The holes are spaced on the PCD 2 at 75mm apart the third at equal distance from the other two. The existing studs have enough thread to take up to 16mm of spacer. Near the bottom of the cone are two mounting brackets. The slotted hole on these will need slotting upwards to accommodate the lowering of the cone by the spacer, and the amount added. It is also possible to bend them upwards to a degree. Another way is to cut the cone under the top flange, and extend it. The shock absorbers have plenty of length to accommodate this within reason I hope you find this of use. John.

Lee. I will measure up the spring seat dimensions for the rears along with pictures of the spring cone to give a better idea of whats required. These could be turned in aluminium, steel, or plastic based material to a height of your choosing. I will also give sizes for a spacer at the top of the spring cone as well as this is a good alternative method of raising the rear of the car. John

The requirement to add 5% ethanol does not cover all suppliers. Those companies that supply below a certain number of ltrs per year, "and I cannot remember what that figure is" are exempt. If you are lucky enough to live by such an independent filling station you can buy ethanol free fuel that will give more mpg. John.

The law allows for up to 5% ethanol to be added to fuel without any notification at the pumps. If the fuel contains more than 5% ethanol it is required that the percentage is shown clearly on the pump. Ethanol has a lower calorific value than petrol, and as such reduces the mpg of fuel when added. Ethanol also dissolves some plastics, and paintwork. Problems have arisen with motor bikes, and boats with plastic fuel tanks. John.

It is most likely that the back plate is bent. If the hub bearings were failing the disc would rubbing at the top of the back plate. A bent drive shaft would show as rubbing the entire edge of the back plate, and you would have what looks like a buckled wheel as it rotates. John

I will have a go at removing the button tray, and see what I can come up with. I have the circuit diagram for the mirror operation, but for the life of me I cannot find a reference to the operating button in the drop down tray. John

If anyone can tell me how to get at the back of those buttons in the drop down tray. I believe I can come up with a simple wiring diagram to make the mirrors auto fold when the doors lock, and unlock. John.

The shoes tend to ware at one end more than the other. If it looks like the linings are down to about 1mm at the thinnest end replace them. It is entirely up to you, but I see little point in replacing the shoes unless they are worn out as they have a very long life with normal use. John.

You may not need a bolt to remove the disc. Often the disc will pull off once the caliper has been moved clear. Any standard 8mm bolt "preferably two" an inch long or longer, and available from any hardware store or places like B&Q will suffice if the disc proves stubborn to remove. John

The play is due to ware, and the reason adjusters are fitted. Under ideal conditions the shoes would not ware, but everyone has the odd lapse and moves off with the parking brake still applied. The shoes are very small and have as said previously very thin linings bonded to them. Even when new I doubt there is more than 3 or 4 mm of material on them. Adjusting the rear brakes will cause less ware on the brake cable because there will be less movement of it to operate the shoes. John.

The parking brake has adjusters in each rear drum. Adjustment may be all you need, but while the wheels are off to adjust the brakes it only take minutes to remove the drums to check the brake linings. The linings are thin even when new because in theory they are never in contact with the drums while the car is moving. John.

Unfortunately diagnosing a problem like this from a distance is near impossible. My first port of call would be any fuse in the circuit, but invariably if a fuse has blown it's blown because there is some other fault such as shorted wiring or faulty motor. Loose connections are another possibility as far as no operation is concerned along with stuck limit switches. Going through the system with a multi meter methodically should give quick results. John.

Perhaps something you already know it makes no difference to the ride height how bad the shocks are. The bushes at the bottom of the shocks can affect the ride height to a small degree. The ratio of increase in ride height to the increase in spring supported shock length is about 1.5 to 1. An inch of extra length at the bottom of the shock will give a ride height increase of 1.5 inches. This is due to the pivot point of the bottom arm shock point being around 2/3 thirds along the length of the bottom arm with the hub mounted at the end. John

Lee I have measured my car, and the measurements are:- NSR 375mm OSR 370mm NSF 385mm OSF 380mm The best place to put a spacer is between the top of the spring cone, and the body. The three studs have plenty of length to accommodate a spacer of 1/2 inch or more. The other relatively easy place to fit a spacer is on the top of the spring where it meets the cone. I hope this helps. John

Lee I will measure my car in the morning "I am not at home at the moment", but I am sure my car is very similar to yours sitting lower at the rear. As you know I also have a tow bar fitted, but have not come across any problems while towing even with the largest dismantle-able mobility scooter, and batteries in the boot. I do have to remove the jockey wheel from the van when on the move to prevent this from touching speed humps. I to would like more clearance at the rear, and with my car it is not down to tired springs or shocks. The spring isolator's are well compressed on my car, but this would not account for 1 to 2 inches of extra ride height I would like or needed to bring the car level. I have considered the idea of fitting a 3/4 inch thick aluminium ring either on top of the spring or suspension top mount. I calculate this would raise the car about 1.5 inches at the rear. John.

I agree, but the difference is not as large as the variation when checking tyres hot as both the speed driven, the duration, load carried, ambient temperature, and possible under or over inflation in one or more tyres would affect the readings

Cold pressures are considered to be the temperatures of the tyres after standing for 2 hours minimum without being driven. John.

Just put them in storage till they are 40 years old. John.

As Collin has already asked are you sure your in D and not B mode. I found when I drove both the Prius, and the Ct it was easy to accidentally knock the leaver, and enter B mode. This gives engine braking for long downhill runs, and just this effect..However the dash display clearly shows your in D mode. If the HV battery is fully charged "all green bars" you can also get this as the electricity generated has no where to go so power generated by MG2 goes to MG1 to spin the engine at speed to give engine braking. John.