Grande rear Springs

[ywork Member Find all posts View Profile Close ywork]

Hi there, I have replaced the front springs with KTFR-101 and kept the standard shocks. Very happy with the resualts.But want to know if anyone has done the same with the rear springs. If I change them and still keep the standard shock will this have an impact on the levelling system? Would be good to know if anyone has just changed springs on the rear of a Grande if so what brand .Im thinking to go with the kings as I have them in the front end.

[Way2go Member Find all posts View Profile Close Way2go]

The Grande doesn't have rear springs.

The rear suspension consists of shock absorbers and airbags - it is the airbags (and associated compressor) that are used to control the rear height (Lo - N- Hi) plus the self-levelling.

The rear airbags can be replaced, but usually only if the current ones are leaking or you install longer airbags for a lift (which you wouldn't do if the front is standard height, and you certainly wouldn't do if retaining the standard shocks as they aren't long enough). There is no such thing as a 'stiffer' airbag for use as a replacement.

I have the extended airbags in my Grande, with longer shocks, as I have the KTFR-101HD with Bilsteins in the front giving me a decent lift.

[Peterpilot Avid PP Poster! Find all posts View Profile Close Peterpilot]

Hi there, I have replaced the front springs with KTFR-101 and kept the standard shocks. Very happy with the resualts.But want to know if anyone has done the same with the rear springs. If I change them and still keep the standard shock will this have an impact on the levelling system? Would be good to know if anyone has just changed springs on the rear of a Grande if so what brand .Im thinking to go with the kings as I have them in the front end.

As W2G said, you can't easily replace the rear airbag suspension with conventional steel springs. It is possible, but you would lose the self levelling system which is an integral part of the air suspension.

Instead, what you may need to do is adjust the rear ride height to match the front since the front is now raised by the KTFR-101 springs.

First measure your front ride height from the bottom of the rim to the guard like this:


Then adjust the rear ride height to about 20mm higher than the front but no more than a maximum of 800mm at the rear with standard shocks. To do this you will need four 30mm M8 bolts and four M8 spacers of about 5-7mm thickness: http://www.pradopoint.com/showthread...l=1#post280029

Or you could use some panel washers as spacers instead: http://www.pradopoint.com/showthread...l=1#post317717

Just remember not to exceed 800mm at the rear with standard shocks.

[ywork Member Find all posts View Profile Close ywork]

Thanks Pete, this is good info. If I put in the spacers as you mention max 7mm, be it washers or spacers. Do I then need to change the settings on the sensor its self or can I leave it as is now that I have put the spacers in under the sensor bracket. And also don’t want to change the airbags. As is now with factory settings set on High the measurement as you showed at the back is 830mm set on Normal its 785mm.This is with the standard TERMS shocks. You mentioned not to go more than 800mm with standard shocks. So if I put in the 5-7 mm spacers to give the lift on normal ride hight, its surly going to go more than 800 when set on High?

[Hutch Addicted PP Member Find all posts View Profile Close Hutch]

Ywork the rear does not have springs, it has an airbag and shocks!


Hutch- 2007 V6 GXL.
2012 V6 GXL on order.

[Peterpilot Avid PP Poster! Find all posts View Profile Close Peterpilot]

Thanks Pete, this is good info. If I put in the spacers as you mention max 7mm, be it washers or spacers. Do I then need to change the settings on the sensor its self or can I leave it as is now that I have put the spacers in under the sensor bracket. And also don’t want to change the airbags. As is now with factory settings set on High the measurement as you showed at the back is 830mm set on Normal its 785mm.This is with the standard TERMS shocks. You mentioned not to go more than 800mm with standard shocks. So if I put in the 5-7 mm spacers to give the lift on normal ride hight, its surly going to go more than 800 when set on High?

The spacers will raise the rear suspension by a ratio of 3:1 without needing to touch the sensor adjustment at all. A 5mm spacer will give you a 15mm lift and a 7mm spacer will give you a 21mm lift.

The 800mm maximum I suggested for standard TEMS shocks is at the "N" or normal suspension setting. If your rear is already at 785mm when set to "N" I suggest you use 5mm spacers to raise the rear to 800mm when in "N". Then when you set the suspension to "Hi" the rear will rise by approx 35mm to 835mm, which should still be OK for the standard TEMS shock for occasional use. Just remember that when in "Hi" at 835mm, you will only have around 45mm downward suspension travel (droop) left.

What did you get when you measured the front ride height of your Prado?

[ywork Member Find all posts View Profile Close ywork]

Thanks for the advice Peter, the front is now 755mm with the new springs. So got a 15 mm lift, but in saying that the old springs were rather tired. I want to put on a set of 265/70 profile tyres, they will also add to better ground clearance.

[Peterpilot Avid PP Poster! Find all posts View Profile Close Peterpilot]

Thanks for the advice Peter, the front is now 755mm with the new springs. So got a 15 mm lift, but in saying that the old springs were rather tired. I want to put on a set of 265/70 profile tyres, they will also add to better ground clearance.

With the front at 755mm the rear should be set at no more than 785mm at the "N" setting, otherwise it will be too nose low / arse high. Remember that the rear will stay at 785mm even when loaded up to the roof as a result of the self-levelling air suspension. At this height, when you set the suspension to "Hi" it will rise to around 820mm and still give you a good 60mm downward suspension travel, which is the generally accepted minimum droop.

As a comparison, an unladen GXL Prado 120 when brand new on the showroom floor was 750mm front and 780mm rear. This could be expected to drop to around 770mm or even less with a load in the rear, without the ability to self-level or to raise to a high setting.