Urethane RTABs & IE toe/camber kit

[lpcapital]

What's the general consensus on these stuff among the 318ti guys?

I've a Z3 which share the same rear end and I'm upgrading the subframe mounts with urethane to avoid the infamous cracks in the differential mount and since I have the subframe off I was thinking about the camber/toe kit to reduce a little bit the camber after I lower the car. The urethane RTABs would be to upgrade the current RTABs.

Do the RTABs squeak or don't squeak? Is the camber/toe kit useful or not?

Thanks guys!!!!

[1996 328ti]

Polyurethane squeak, especially when cold.
I don't know what the subframe mounts have to do with the diff mounts.
Has that been a problem?

Unless you car is not tracking straight or getting uneven wear, I wouldn't bother with the IE kit. Now my car on the other hand, skews to the side under hard acceleration and really should have the kit installed.

[lpcapital]

Originally Posted by 1996 328ti

Polyurethane squeak, especially when cold.
I don't know what the subframe mounts have to do with the diff mounts.

Unless you car is not tracking straight or getting uneven wear, I wouldn't bother with the IE kit. Now my car on the other hand, skews to the side under hard acceleration and really should have the kit installed.

Te car pulls straigth... However the rear aligment is off and I suspect is the trailing arm bushings.

The diff is bolted to the subframe, while the hear is attached to the trunk floor: when cornering the subframe moves because of the soft bushings and the diff pulls on the trunk floor. Adding the urethane bushings on the subframe mounts avoid he subframe to moove therefore the diff doesn't ripp off the trunk.

The IE kit would be nice to reduce some of the camber when I lower the car: I don't like to have 3 deg negative in the back since i think the car looks a little stupid, that much camber is not necessary, and the car is my DD and I don't wanna go through a set of tire every 30K miles or so...

[cooljess76]

I'd recommend the IE kit. It's fairly inexpensive and will save your tires. That's first on my list of things to do once I get my car running.

[Mallard]

i run a few different powerflex items on mine, not noticed that much difference tbh.

I do have a very hars susp. setup on mine, so i think its hard to determine the difference between them in my case

Havnt heard any squeeking thought

[lpcapital]

Originally Posted by Mallard

i run a few different powerflex items on mine, not noticed that much difference tbh.

I do have a very hars susp. setup on mine, so i think its hard to determine the difference between them in my case

Havnt heard any squeeking thought

Do the RTABs need to be lubricated constantly or just when installed? I think they should be mounted with some silicon grease which I beliece IE supply. So far than a lot you guys (on these technical stuff you are far better than the Z3ers, let me tell you... eheheh)

[1996 328ti]

Originally Posted by lpcapital

Do the RTABs need to be lubricated constantly or just when installed? I think they should be mounted with some silicon grease which I beliece IE supply. So far than a lot you guys (on these technical stuff you are far better than the Z3ers, let me tell you... eheheh)

Mine were lubed a couple times. It didn't last long.

[Mallard]

i lubed the rtabs after fitting because i forgot

but they never squeeked anyway

[lpcapital]

I wander if the squeaking is a problem of the IE only. I asked Jeff Ireland of IE and he said he has never heard of it.
Anyway, lubricating makes sense being the reason... Not sure why, but lots of people appear reluctant lubricating moving parts.

I managed to drop the subframe today. Here's a couple pix:





A couple questions:

1) can I separate the output shaft from the diff by pulling it off or that's something that I should be careful to avoid?

2) the outer u-joint on the driveshaft is acting weird: it pivot freely around one axle, but around the other axle it clicks and then start moving freely (hopefully it makes sense... ehehehe my technical English still have a lot to improve... ehehehe). I just wanted to know if this behavior is normal.

Thanks guys!!!

Keep the comment on the urethane RTABs coming, they are very helpful. The IE camber and toe adjustment kits are going on for sure; I just need to find a shop with the experience on how to properly weld them.

[dave45056]

I went thru this same dilemma not long ago.
Here is what I ended up doing:
IE kit for Toe and Camber... (actually I made my own using 5 series eccentric bolts and some simple weld on plates)
Stock RTAB's lube with WD-40 at install.
Stock subframe bushings with custom urethane inserts.
Here is a link the the thread where I documented it:
http://www.318ti.org/forum/showthread.php?t=22672

As for your questions... The Driveshafts come off of the diff by unscrewing the 6 bolts around the flange. They are external torx bolts and are tight. Usually you would pull them off before disconnecting the driveshaft as that would keep hold the diff from spinning inside. Also If you do it while still in the car it is easier to put some muscle behind it. Not sure if air tools will help with these bolts.

I don't know the answer for sure about the u-joint. Maybe someone else can help.

One more thing... Since you are this far in, I would highly recommend doing the rear bearings unless they were done recently. You are 1/2 way there already.

[TI-driftin]

Yes i recommend the IE kit too. My camber and toe was out and couldn't be adjusted. The insides of my tires were getting eatin up especially due to the toe. Put The kit on and lowered my car with hr sport springs and they aligned right in spec.

If you or a friend can weld just do it yourself. What i ended up doing was bolting the plates on to the outside of the existing brackets, marked them up, took em off and slotted the existing holes on the stock brackets, then welded the plates on the outside of the old mounts. Worked great saved me the trouble of cutting a square out of the old brackets.
I had my friend weld them and he welded one side on a little crooked and the shop still had no problem getting it aligned to spec, so i don't think you have too much to worry about. Mine does squeak though.

[lpcapital]

Aight guys, here's some updates and a couple other questions.

The u-joints on the driveshaft were seizing up so I removed it and dropped it off a local driveline shop (Oceanside Driveline) for a complete rebuild: they replaced the 2 u-joints, central bearing, roll cage bearing and rebalanced it. I'm gonna go pick it up tomorrow. The guibo was cracked so I replace that as well...

I decided to go all out with IE: camber/toe kit, subframe mounts & RTABs. I also got the bottom-mount RSMs...

Here's the question:
1) regarding the toe/camber plates: how would you recommend the positioning of the plates vis-a-vis the existing hole? Here's what I was thinking: for the toe I would position the original hole in the center of the slot to be able to adjust the toe both ways; for the camber I would position the hole more towards the bottom of the slot to be able to have more room to cancel out negative camber once I lower the car. Any take on this?

Also I would like to share this reading regarding the installation of urethane bushings. Particularly: "The real tip here is to use plenty of the supplied urethane grease (or anti-seize) anywhere that metal touches urethane. Screw this step up and you will eventually have maddening squeaks over every bump. One important thing to remember is that urethane bushings operate in a completely different way from stock. The stock rubber bushings are solidly attached to both the outer (control arm) sleeve and the inner sleeve, and the inner sleeve is clamped down and prevented from moving, so the suspension movement is the result of the rubber twisting. With urethane bushings, the inner sleeve actually rotates inside the urethane. So with the stock rubber bushings, there is nothing moving, as nothing needs lubrication. But with urethane bushings, the interface between the bushing and inner sleeve (and also the outer mushroom-shaped caps) needs to be lubricated."

As I though the trailing arm works like the hinges of a door... And when a door squeaks you lubricate the heck out of it until it quits. I'll see how that one goes...

[TI-driftin]

Originally Posted by lpcapital

Here's the question:
1) regarding the toe/camber plates: how would you recommend the positioning of the plates vis-a-vis the existing hole? Here's what I was thinking: for the toe I would position the original hole in the center of the slot to be able to adjust the toe both ways; for the camber I would position the hole more towards the bottom of the slot to be able to have more room to cancel out negative camber once I lower the car. Any take on this?

.

Im just guessing here but if you position the camber like that you may not be able to adjust it enough to get out of the positive camber range, unless you plan on lowering the car 2" or more. I centered both the plates for toe and camber and the specs came out with positive camber. I even lowered the car 1.25" in the rear. The shop had no prob getting it back to factory settings, which does have some negative camber. I dont think that will give you a tire wear problem. At least not as much as the toe does

[mohaughn]

While the way you guys are talking about installing them probably works, that is not the way they are designed to work.

You really should be grinding the stock brackets off, and then welding in the new ones... I know it is more work, but do it once, do it right.

If you already have the entire subframe dropped, it is not much more work to cut the existing mounting brackets off.

[lpcapital]

Originally Posted by mohaughn

While the way you guys are talking about installing them probably works, that is not the way they are designed to work.

You really should be grinding the stock brackets off, and then welding in the new ones... I know it is more work, but do it once, do it right.

If you already have the entire subframe dropped, it is not much more work to cut the existing mounting brackets off.

If you mean grind the existing holes to match the slots in the plates, I'm right with you...

If you mean removing the existing trailing arm brackets from the subframe and replacing them with the IE kit... That's the first time I hear it...

Could you clarify what you mean? Thanks