Notice:The location of the A/C drain, and water outflow, seem to have a pronounced negative effect on poly mounts. Jury is out on effect on neoprene. Recommendation is to check the mounts every 6-12 months for wear/degradation. 9/7/13
Key Update: Upgraded engine mounts are reported to address 80% of the issues outlined below and are highly recommended for FI or high power applications. See this thread for details. 1/3/15
Purpose: The purpose of this thread is to keep a master list of all transmission mount options and a description of the effect of the change and the target application (track, street, etc.) as well as some general information about the subject in one easy-to-find place.
Issues: Primarily denial of 2nd gear from higher gears (car will not go into gear 2nd gate is "blocked"). This issue typically arises during hard braking and/or hard turns, especially such that would be found in autoX or the track. Also, drive line flex can mean a less than smooth shifting experience--some report a smoother shifting experience between 1st and 2nd and overall with mounts.
Goal: Reduce the frequency of this issue without making the car intolerable to drive ("intolerable" will be subjective and will be directly related to intended use: street/track).
Scope: This covers the denial of 2nd only and does not address the "1st to 2nd" grinding issue. (That is best addressed through shifting style--slight pause, pull down and to the left; and potentially a change of fluids. Search for more on this if you have this issue).
New information-December 2012. It may be that engine mounts and engine movement are the primary cause of issues, and that transmission mounts are a secondary (and only partial) cure. They do reduce issues, but do not eliminate them. Please see this thread on Engine Mounts for more information.
Updates: I'll try to keep this thread updated as data comes in. ( Also, many thanks to those who have posted on this before, done DIYs, or answered my PMs on this topic!
) If there's a resource or thread I should add please PM me and I'll add it (don't expect me to read every post that may end up in this thread--assume I'm lazy
).
Recommendations: These are based on my research, info submitted by forum members, and personal experience (Rogue neoprene and UUC Red Poly). Please note that YMMD. If you strongly disagree with a recommendation, please PM me some data and your experience so that can be considered for updates to this thread.
Terms: NVH = Noise Vibration Harshness. Poly = Polyurethane. Neoprene = Rubber
Quick Recommendations: Street only: Rogue neoprene transmission mounts, if a little more rawness and mild/mild-moderate NVH is desired, UUC black poly.
Mixed track/autoX + street: UUC poly, or Rogue neoprene transmission mounts, possibly enforcer cups, and possibly Rogue neoprene motor mounts. (Lower NVH w/neoprene.)
Track only: red poly, and probably upgraded motor mounts as well (Rogue neoprene or poly).
Please see details below!!!
Installation: Installing these little babies is a major PITA w/o a lift and not even that much fun with one due to location and limited space. Blind32 has a great DIY as does Billswebspace. An indie shop should be able to install these with about an hour's labor and if you have access to such a shop it's a pretty good option. Over torqueing the nuts (19 nm torque, which is very little) will result is a lot of noise no matter which option is chosen.
The Complications of "Black" and "Red": In various posts and threads mounts are often simply referred to by color. However, the color is not as important as the actual
material. Poly will be louder than neoprene, and it's not possible to equate the results of red neoprene to red poly. To further complicate matters, UUC used to make red and black
neoprene mounts. They have recently changed their production to be red and black
poly. So it is important to keep that in mind when looking at threads/posts where folks have noted their impressions of NVH. Red and black neoprene will not yield the same results as poly!
Transmission Mount Options
Rogue Engineering Neoprene: Improved feel, slightly more notchiness, greater precision. Very slight increase in NVH, most noticeable in reverse or with 1st gear engagement. Seems to cure the 3rd to 2nd gear denial issue for most except in the most demanding situations (where engine movement may also become a factor). Recommended solution for most common applications due to the limited NVH and improved feel.
UUC Black Poly: More NVH due to the use of poly. May hold up better in hotter and more intense applications (track in particular) due to the nature of poly vs. neoprene. Comes with or without enforcer cups. The cups add a bit more NVH (several folks report no increase) but are supposed to decrease transmission wobble even more. When researching here on the forum, please note that while various threads/posts may be useful most of these folks commenting on the UUC black mounts had the earlier rubber version, not poly. Mfanatic has these, which he's installed and uninstalled several times with the end result being they're rather noisy. Recommended for track or heavy autocross use only where the car has fairly limited street use.
UUC Red Poly: Significant increase in NVH. Noted improvements in feel, precision, and a bit more notchiness compared to the Rogue. The NVH drowns out the sound of the S54 and there's a “airplane like sound quality” to the drivetrain. (Skelekitty says it sounds like farmer Ted's tractor.) This is more pronounced under heavy throttle and/or above 3,500 RPM and the NVH increase in relation to increase throttle and RPMs. NVH going into reverse and first can be a bit disconcerting. UUC says "...initial user reports say that it is minimal and certainly acceptable." Depends on who is doing the listening I think. Link Recommended for track or heavy autoX use only where the car has very limited street use.
UUC Red Poly Bolt Through: Not recommended for anything but a dedicated track car.(probably similar to the Vorshlag). I don't know anyone with these, but given how the regular red poly are, they have to expose the occupants to a lot of NVH. Recommended for dedicated track and race cars only.
UUC "Enforcer Cups": These are an optional addition from UUC that are supposed to offer more control. Reports vary. Those using these in conjunction with Rogue neoprene report more control and a small increase in NVH. Some using them with poly report excessive NVH.
Voschlag (Orange or Red): Massive NVH (Z4mnyc has these plus engine mounts and says “the radio is almost pointless”). Recommended for dedicated track or race cars only!
Additional Options and Notes
Engine Mounts: Engine mounts (Vibra Technics, UUC, Vorshlag, or Rogue) can be added to further reduce driveline movement. Adding these and the transmission mounts will practically eliminate any drivetrain slop--this the only way to fully eliminate the denial of 2nd issue. Those who have done this report a full fix under all conditions. Vibra Technics appears to have a solution that does not appreciably increase NVH but does reduce motion while retaining good isolation properties. E46 M3 owners report good results. Please see this thread.
UUC and Vorshlag are both poly this will may be at the expense of your sanity in anything but a fully prepped and dedicated full-time track (or preferably race) car due to NVH. Rogue has a neoprene version out that they claim only increases NVH by ~30%, and is cheaper than the BMW Motorsport version (380 vs. 800+). (BMW Motorsport mounts are just a harder rubber version of stock like the Rogue.) No real data from forum members on the Rogue get, but based on the experience of the neoprene vs. poly mounts it's fair to assume these would have considerably less NVH than poly. (If anyone gets the rubber, please PM me your experience.) Poly are recommended for race prepped cars only; Neoprene for those who want more control over the drivetrain and a smaller increase in NVH.
General Application Notes: In terms of NVH from least to most: Stock -> Vibra Technics -> Rogue -> UUC Black -> UUC Red -> Vorschlag. As someone noted the other day on the forum engineering/design is always about compromise.