The TT has conventional coil springs and shock absorbers coupled to a very sophisticated suspension design , some TT's (JZZ30) models had TEMS (Toyota Electronically Modulated Suspension), the TEMS controls the damper rate in accordance with road speed and use of the ECT switch (Electronic Controlled Transmission) which is similar to the sports mode found on other automatics, on the TEMS equipped cars you get both sports suspension and transmission from the ECT switch in PWR.

There appears to be another type of TEMS fitted to later TT's called REAS, (a Reactive version of TEMS), this system may be found on cars which have the wired in suspension turrets but lacking the TEMS stickers.

Creaks & Squeaks:

The suspension can develop annoying creaks, more so in the dry summer weather even in England. This is caused by the suspension mounting bushes drying out and creaking or clicking as the arms move up and down, applying "white" grease from a spray can to all the suspension mountings (including the anti-roll bar mounting rubbers) and the sub-frame mountings will alleviate this but the real cure is to open each mounting sufficiently to force the grease into the surfaces where the bushes touch the frame (carefully drive the car with the suspension mountings loosened to work in the grease),  removal and greasing of the mounting bolts is also a good idea.

Bangs & Clunks:

The Lower front arms have bushes fitted on the inner ends, these bushes wear after several years and cause a dreadful sounding "CLUNK" from the front end, normally noticed if you brake when going backwards and then again the first time you brake when going forward. Toyota only sell the bushes fitted to the lower arms (about £300+tax in the UK). Our Oz guys have manufactured replacement bushes in Blue Nolothane which is a touch harder than the originals but not noticeably so, these cost about $35 AUS ( about £13 GBP) each. I am told only the two rear most bushes need changing on each lower arm so replacement is just two bushes costing around £26 GBP, we are getting several sets sent over from Oz by Rob Hayden of the ALSC so we can reduce the shipping costs, contact Powerhouse if you need any in the UK as they should soon have a couple of sets on stock. 

Iain Wiltshire has always maintained that the current bushing is not suitable for wheels beyond 16" as they are too soft to take the additional lateral forces, fitting the harder bushes rearmost on the arm will allow for 18" rims, fitting the Nolothane bushes to the front and rear mountings will accommodate 20" rims. There are differing Toyota part numbers for the lower arms on the JZZ30 (UZZ30/31 are the same), as the physical dimension is the same it can only be the bushing that is different, a point to note here is the bottom ball joint, if this has any play it will require the complete arm to be replaced.

The JZA80 Supra appears to share the same bottom arm (again different part numbers - same dimensions) so this mod would be useful for any Supra owners with Clonking suspension or wanting to stiffen the front suspension mountings.