Earlier this year, I discovered that my recently purchased and still under warranty 2004 GT had suspension problems, even more than those mentioned in this forum at various times (see threads re "Why is GT suspension crashy"). The wheel arch to tyre gaps on my car were uneven (approximately 50mm difference from side to side, both front and rear) and the car was frequently scraping the front right hand side when going over culverts, etc. I eventually took the car, which was only 2 weeks out of warranty, to the Alfa Romeo dealer who sold the car to the original owner and asked them to check the problem. They said that as the car was out of warrenty, they would not be able to do anything about it, even though they verified the suspension problem. I tried to reason with them that the problem was a previously known problem as the previous owner had replaced the RHS rubber deflector which had been trashed after frequent scrapes on the ground.
So, as the harsh ride (frequent crashing on bump stops) was really annoying me, I decided to purchase a set of Bilstein struts (item numbers front BIL-BE3-2797 and rear BIL-VE3-4721) and Eibach springs (item number E-1010-0040222) for both front and rear. I also purchased a Q2 diff centre to be replaced at the same time as the suspension upgrade.
Well, last week I took the plunge and replaced all struts, springs and the Q2 diff. A HUGE job but one that I was able to do myself in my home workshop. Admittedly, I do have a hoist and a good set of tools. And guess what, the rear spring heights were 50mm different - one of the springs had collapsed!!!!! The uneven lengths of the rear springs had been reflected into the front suspension geometry as well causing one side to drop lower than the other.
Now that the car is back on the road, it feels completely different. The suspension is just brilliant with no more crashing and banging. I deliberately drove over every pot hole, man-hole cover, rut, etc., and not once did the suspension get caught out. This is how the car should have been built originally! The Q2 diff also makes the car feel different with fantastic turn-in and no signs of understeer.
The attached photos show how the Q2 diff is fitted. It can be removed and refitted without removing the gearbox. The engine needs to be supported carefully as the entire subframe and the rear engine mounting are removed. Fit new bearings to the Q2 diff centre (same as the originals) and there is no setting up to do. The bearing pre-load will be the same as before so it is a straight changeover. Just make sure you refit the spacer washer. See additional photos in associated thread.
So, if any of you GT owners out there are frustrated with the suspension, give it a birthday set of new springs and dampers (and of course a Q2 diff centre at the same time) - you will be smiling
every time you go for a drive and no more scowls