99 GS

What is the sway bar size for the front and rear? I have heard 18mm front, and 12mm rear; is that true?

19mm in the front, 13mm in the rear.

Teklein is right
if you upgrade most people upgrade either the rear to 19, or both to 21.

Originally posted by teklein
19mm in the front, 13mm in the rear.

I was researching the diameter of the stock front & rear sway bars so I could purchase new bushings and come across this old thread. Those numbers didn't sound right to me so I did some more searching on other sites and come up with this:

Base / Rs / Gs / ESi
Front: 16mm
Rear: 12mm

GSt / TSi-Fwd
Front: 18mm
Rear: 15mm

GSx / TSi-Awd
Front: 19mm
Rear: 18mm

I just thought I would share this information for the sake of future searches. This was the only thread I could find on 2gnt regarding stock sizes and the previous stated information was false. 19mm sounded too large for a stock front bar on an N/T and 13mm rear just didn't sound right at all.

Already I am going to point out something:

1. Base and RS versions did not have a rear sway bar.

2. You say that a 13mm in the rear does not sound right and that it is 12mm? That 1mm is what tipped you?

3. By "searching on other sites" what are you referring to? Tuners? I am interested in seeing your references if you do not mind. Not saying I doubt you personally, however unless you took a dial caliper to all model sway bars personally I would like to know the source.

According to CAPS,

All FWD platforms share a rear sway bar part number of MR130722.
All AWD platforms share a rear sway bar part number of MB914340.

Non-Turbo models had a front sway bar part # of MB910391 or MB871885.
All Turbo models had a front sway bar part # of MB871885.

MB910391 is 16mm
MB871885 is 19mm

These are OEM specifications.

Think logically: Is a manufacturer going to spend money on producing and stocking three different rear sway bars and three different front sway bars for a total of 6 parts to share across trim levels of a vehicle? No.

1. Note that Gs and ESi is also listed. I didn't feel the need to break the list down to just Base/Rs & Gs/ESi because they all share the same size front sway bar.

2. The reason 13mm didn't sound right is because I have never seen an after market bushing available from Prothane or Energy Suspension for the Eclipse/Talon in that size. The whole reason I started researching sizes is so I can replace my bushings. I was trying to figure out why 3 different sizes were offered and which size I needed.

3. CAPS was my reference. I don't use the CAPS on 2gnt. It is incomplete and doesn't link you to all part numbers.

Here's the 3 part numbers for the front sway bar.
MB910391 16mm
MB864694 18mm
MB871885 19mm

Here's the 3 part numbers for the rear sway bar.
MB948100 12mm
MR130722 15mm
MB914340 18mm

Six different bars do exist. The convertible might or might not have a play in the different sizes.

My sway bar sizes came from the 2gnt specs out of the wiki.

19mm in the front does sound kinda funky though, only because (unless im reading wrong) FWD RM kits come with 19mm and AWD has 21mm. Or maybe FWD and AWD RM kits come with 19mm...