Finally, I've got a height adjustable driver's seat

[nyprius]

<div class='quotetop'>QUOTE(Solar_Powered @ Aug 2 2006, 07:32 PM) [snapback]296623[/snapback]</div>

Yes, I'm one of those tall drivers who has desired a lower driver's seat so you can see better (there has been many topics discussing this subject).

Also, in the past, I posted the instructions "Move up the Rear-View Mirror for better forward vision"
( http://priuschat.com/index.php?showt...0285&hl=mirror )
so you can see the "tall driver's syndome" runs strong in me!

Finally, after a lot of research, thought, planning, a trip to Japan, and bit of sweat; you'll find the results of my quest as the attached .PDF.

I hope this will be useful to others on PriusChat!
[/b]

Thank you for this excellent post! I'm not sure I'd have the patience or ability to do all the work you've done. Having studied the seat extensively, do you think it would be possible to drill lower holes in the four pieces of metal extending up from the seat rails that hold the seat in place? It appears I could do this then bolt the seat at a lower position. If I sold the car, I could return it to normal. What do you think?

Also, it would be great to know if it's possible to get a height adjustable LHD seat from Europe and what it wold cost? Toyota ought to start making these available for US Prius's. Providing these seats for free or at a nominal cost would partly make up for the mistake of not providing height adjustable seats in the US, as they are provided in Japan and Europe.

[grasshopper]

WOW! ...... I am completely speechless and in total awe.

[Solar_Powered]

darelldd asked, "it would seem that modifying the Japan factory seat left-to-right would be an easier task?"

The "pump handle" height adjustable mechanism (and many of the other seat related assemblies) are fabricated using large flat rivets. These rivets are also very low profile, often so the heads can clear other parts of the assembly. As rivets of this size are typically assembled in a multi-ton press, it would be difficult to find a fastener of equivalent size and strength to replace them. I'd estimate a left-to-right swap of the mechanism would be actually more difficult than the seat retrofit I did.


naterprius asked, "does the seat sit any further back now that you are done?"

No, the retrofitted height-adjustable seat mounts exactly to the floor as the original Prius seat, so there is no additional leg room as a side benefit.


nyprius asked, "Having studied the seat extensively, do you think it would be possible to drill lower holes in the four pieces of metal extending up from the seat rails that hold the seat in place?"

Actually, that was my original plan. But on close examination of the complexity of the rear mounting structures, I abandoned that plan. Additionally, as my wife is about 1 foot in height shorter than I am, I was highly motivated to focus my attention on the height-adjustable solution so we both could drive the Prius comfortably.


Many have also mentioned that purchasing a Prius seat from Germany might also be a good solution; I agree. Hopefully a German based "Prius Chatter" can answer the question, "Does a Prius in Germany come equipped with a factory height-adjustable seat? And, "How much does such a seat cost as an aftermarket item?

[nyprius]

<div class='quotetop'>QUOTE(Solar_Powered @ Aug 3 2006, 02:13 PM) [snapback]297088[/snapback]</div>

nyprius asked, "Having studied the seat extensively, do you think it would be possible to drill lower holes in the four pieces of metal extending up from the seat rails that hold the seat in place?"

Actually, that was my original plan. But on close examination of the complexity of the rear mounting structures, I abandoned that plan. Additionally, as my wife is about 1 foot in height shorter than I am, I was highly motivated to focus my attention on the height-adjustable solution so we both could drive the Prius comfortably.
[/b]

Thanks! Clearly the fix I was suggesting wouldn't work if there were two drivers of different heights. I'm the only driver of my car. If someone short needed to drive it, I'd give them a pillow.

Can you say more about the rear mounting structure? As far as I could tell, there seemed to be four triangular pieces of metal coming up from runners in the seat rails. The points of the triangles were at the top. There was a hole through each triangle near the top, to which the seat was bolted. The metal was partly bent for stength, but that didn't seem to preclude drilling a lower hole to which the seat could be mounted, possibly with longer bolts if necessary. What was it about the rear supporting plates that made this seem not viable?

[grasshopper]

In the end, how much lower would you say the seat can go? (Front/rear)

[Solar_Powered]

nyprius asked, "Can you say more about the rear mounting structure? As far as I could tell, there seemed to be four triangular pieces of metal coming up from runners in the seat rails. The points of the triangles were at the top. There was a hole through each triangle near the top, to which the seat was bolted. The metal was partly bent for strength, but that didn't seem to preclude drilling a lower hole to which the seat could be mounted, possibly with longer bolts if necessary. What was it about the rear supporting plates that made this seem not viable?"

Nyprius, you need to spend a lot more time taking your Prius apart!
If you look at the attached .JPG of the rear mounting structure, I've added red lines where the support bracket is hidden by the other structure.

Let's say we want to pull out the lower two bolts, and drill two new holes higher up in the support bracket; the lower bracket will interfere with the seat sliding rail. OK, let's say we want to drill out the upper rivet and remove the about 18" long "rivet pin" that passes through the tubular brace, and drill two new holes higher up in the side structure of the seat; the resultant lowering can only be about 1/2" before the support bracket interferes with the beige plastic trim piece.

My conclusion (and you can draw any conclusion you want to) is that the only way to make a permamently lowered seat is to remove a "strip" of steel from the support bracket, effectivelty shortening it, and re-welding the bracket back together.

[nyprius]

<div class='quotetop'>QUOTE(Solar_Powered @ Aug 3 2006, 08:51 PM) [snapback]297400[/snapback]</div>

Let's say we want to pull out the lower two bolts, and drill two new holes higher up in the support bracket; the lower bracket will interfere with the seat sliding rail. OK, let's say we want to drill out the upper rivet and remove the about 18" long "rivet pin" that passes through the tubular brace, and drill two new holes higher up in the side structure of the seat; the resultant lowering can only be about 1/2" before the support bracket interferes with the beige plastic trim piece.

My conclusion (and you can draw any conclusion you want to) is that the only way to make a permamently lowered seat is to remove a "strip" of steel from the support bracket, effectivelty shortening it, and re-welding the bracket back together.
[/b]

Thanks again Solar_Powered! This is excellent info! I was looking under the seat while it was in the car. So I couldn't see exactly what was going on. Your picture helps a lot. Even lowering the seat a 1/2" would make a noticable improvement I think. If I wanted to lower the seat an inch, the ideal amount for me, it seems I could trim or file off some of support bracket. I'm pretty sure the supports are meant to shear off in a severe accident. I'm concerned that welding might limit the ability to shear. Of course, what I'm suggesting might affect shearing as well, but probably not as much.

Your pictures shows the bracket bolted on the bottom but riveted on the top. I can't see the other side of the rivet. Do you know if it's bolted or riveted on the other side? It looks like it might be difficult to drill out the rivet. So I was hoping the rivet is a fixed post with a bolt on the other side.

[Sho-Bud]

In The Netherlands, all Priusses have the height adjustable driver seat.
I called the parts department of the dealer.
The chair consists of loose components which can be bought seperately.

[nyprius]

<div class='quotetop'>QUOTE(Sho-Bud @ Aug 4 2006, 03:23 AM) [snapback]297543[/snapback]</div>

In The Netherlands, all Priusses have the height adjustable driver seat.
I called the parts department of the dealer.
The chair consists of loose components which can be bought seperately.
[/b]

Thanks Sho-Bud! Do you know what the whole seat would cost in tan fabric? Alternatively, could you provide a website or phone number where I could get this info?

I had the seat rails extended on my Prius so it slides back three inches further, providing a lot more leg room. I assume I could take the rails off the old seat and put it on the new one. Though, I'd have to check if the height adjustable and non-height adjustable seats have the same rails.

Toyota should make this seat available in the US. US Prius owners shouldn't have to deal with the cost of shipping it in from Europe. Also, I wonder if the seat would make it through customs. Or does it need USDOT approval before being used in the US.

This is as much a safety as a comfort issue. My visibility is significantly restricted out of the front and rear windshields because I sit too high in the car. This means not providing seat height adjustment, as it is provided in Japan and Europe, increases the chance of having an accident, as well as substantially decreases driver comfort. For the safety and comfort of their loyal customers, Toyota ought to make it easy for US Prius owners to replace their driver's seats with ones that have height adjustment.

[Solar_Powered]

<div class='quotetop'>QUOTE(grasshopper @ Aug 3 2006, 04:18 PM) [snapback]297225[/snapback]</div>

In the end, how much lower would you say the seat can go? (Front/rear)
[/b]

The rear of the seat (i.e. headroom) moves down about 2 inches lower than the original Prius seat, and the front of the seat (i.e. thighs) moves down about 1-1/4 inches.