jvah1980

Hey folks,
I have a 2006 is250 awd with Megan racing coilovers. Their is virtually no gap (25 inches from fender to ground).

I bought the car like this. There is a slight shake/vibration under acceleration. Similar feeling to tires out of balance.

I read lowering a AWD IS can cause a lot of weird issues including bad cv joints (one is already getting replaced because it's leaking) and shakes under acceleration.

This may be a stupid question, I don't know anything about coilovers. If I adjust the coilovers to a ride height similar to factory, will everything be similar to the standard factory suspension? Or is the setup of a coilover going to behave differently at normal ride height just because it's a coilover?

Thanks

SeanO

iTrader: (1)

There should be dampening adjustment on those coilovers but I don't have them so I can't be sure. That will adjust how firm or stiff the ride will be. Just raise it up about an inch and it should be fine.

Icy350

iTrader: (18)

Megan's are fully adjustable.

More height = more clearance = less chance of rubbing.
The stiffness and softness can be adjusted by turning the ***** on the top side of each coilover (however being that you are not familiar i would seek professional help to make sure your settings are good)

AWD who are lowered are like a niche within a niche. Handful were able to drive just fine, while the other had severe vibrations and I even remember reading about 1 guy who completely messed up his AWD. I believe that as long as you get the rolling diameters in the green, you should be alright. but again, seek professionals to help you carry it out.

jvah1980

Wow wow wow!!!!

Thanks for the info guys.

So, I did a few things this morning. Mainly I raised the ride height about an inch all around. What I found was the previous owner had them all completley different. None of them measured (measuring from the bottom of the top nut to the sleeve underneath the bottom nut of the adjustable shock).

There was a major discrepancy between the front and the rear. So much so, I thought maybe they should be measured differently. It seemed according to Megan's site they should all be set the same. I went around and measured them all exactly the same. The measurements I got from the ground to the the fender was within a 1/2" of 26 all around. I don't have a flat surface so it was hard to tell if they were uneven, or just different due to the uneven and lopsided surface.

More important, IT"S LIKE A BRAND NEW CAR!!! There is the Lexus ride I was looking for. All shakes (including shakes I was certain were tire balance shakes) completely eliminated. I was getting a mild vibration when idling in gear - that is now completely eliminated. This car is like a dream now! The transmission always felt clunky, like it shifted hard from gear to gear (never slipped or anything to cause serious alarm), but far from smooth. Even that feels better (although 1st to 2nd is still pretty jerky - and the smoother transmission could very well be in my head).

I'd give a BIG upvote to NOT lowering an AWD IS250. Although, at around 26" all around I'm pretty sure I'm still lower than stock. I don't know what stock is, but I think the car looks good as-is, and drives awesome - and in the end that's all that matters!

I may shell out for the Lexus tranny-flush now. I did read some people saying with the equipment they have Lexus can now do a complete flush and refill of the sealed system and that some people found smoother shifts.

Icy350 - what do you mean "rolling diameters in the green?"

Thanks!

Aspect

^"Rolling diameters in the green - referring to the diameter of the rim + tire has to remain unchanged or remain within a 5% margin. So if you started with the stock 17s with 225/45/17 -> 18s 225/40/18 -> 19 225/35/19 etc. When the coilovers were installed the fender to ground measurements were probably equal, but it's possible that they didn't readjust the height when the coilovers settled in. The front and rear don't have to be set the same, the previous owner might have liked the look more.