Allroad transmission mount conversion...
10-14-2004, 06:38 PM
#1
AudiWorld Super User
Thread Starter
Allroad transmission mount conversion...
<center><img src="http://pictureposter.audiworld.com/711/artmi1.jpg"></center><p>
The day started so well. Beautiful out, crisp, cool and sunny and I was REALLY up for this adventure.
Up until about 3 minutes after I took this pic the world was my oyster. This is a pic of a B5 chassis stock OEM transmission mount in my B4 chassis 90 Sport Quattro. I knew since these are a direct swap that the Allroad would also either work or not work on both vehicles. I opted for the B5 OEM transmission mounts initially due to their stronger, cast aluminum nickel alloy over the the rather skimpy, stamped steel Audi B4 tranny mounts. You can tell by looking at the mount in this pic that its a relatively new mount having fewer than 1500 miles on it.
What I didnt mention to anyone last night is that I was also dropping my sub-frame today and installing new bushings at all four corners and treating my control arms to some homemade Delrin bushings with zerk fittings so they can be re-lubricated with a grease gun. I have a set of Powerflex urethane bushings I bought for this car but there's just something about Delrin that is confidence inspiring and it doesnt have the squeak/squeal issue that urethane can have. Also it's far less compliant but dont let anyone tell you they are teeth jaring, abusive, harsh or "hard" feeling. They most certainly are NOT and if you consider the pivot points they're mounted in you can understand why. That pivot does NOT take the brunt of any suspension component like shock or spring. It simply pivots. Thats ALL it does. I've made or bought Delrin bushings for decades and on many cars and not one was influenced negatively in any way. Its pure precision pleasure to drive a Delrin bushing'd car. And they can be replaced by hand at any time with no hydraulic or arbor press required. Just slip the old out and slip in the new. Cake! And if they're kept lubricated they last forever.
Another benefit to doing at least the first experimental Allroad tranny mount conversion with the sub-frame out of the car would allow me to do the job on a workbench at a comfortable height. If I ran into a snag I could better cope with and solve the issue easier if not working with my hands over my head.
So I pull the left rear sub-frame bolt out and all is going well. Then I get to the right rear. Impact wrench is spinning but nothings happening...Grrr sh*....
continued with next pic
The day started so well. Beautiful out, crisp, cool and sunny and I was REALLY up for this adventure.
Up until about 3 minutes after I took this pic the world was my oyster. This is a pic of a B5 chassis stock OEM transmission mount in my B4 chassis 90 Sport Quattro. I knew since these are a direct swap that the Allroad would also either work or not work on both vehicles. I opted for the B5 OEM transmission mounts initially due to their stronger, cast aluminum nickel alloy over the the rather skimpy, stamped steel Audi B4 tranny mounts. You can tell by looking at the mount in this pic that its a relatively new mount having fewer than 1500 miles on it.
What I didnt mention to anyone last night is that I was also dropping my sub-frame today and installing new bushings at all four corners and treating my control arms to some homemade Delrin bushings with zerk fittings so they can be re-lubricated with a grease gun. I have a set of Powerflex urethane bushings I bought for this car but there's just something about Delrin that is confidence inspiring and it doesnt have the squeak/squeal issue that urethane can have. Also it's far less compliant but dont let anyone tell you they are teeth jaring, abusive, harsh or "hard" feeling. They most certainly are NOT and if you consider the pivot points they're mounted in you can understand why. That pivot does NOT take the brunt of any suspension component like shock or spring. It simply pivots. Thats ALL it does. I've made or bought Delrin bushings for decades and on many cars and not one was influenced negatively in any way. Its pure precision pleasure to drive a Delrin bushing'd car. And they can be replaced by hand at any time with no hydraulic or arbor press required. Just slip the old out and slip in the new. Cake! And if they're kept lubricated they last forever.
Another benefit to doing at least the first experimental Allroad tranny mount conversion with the sub-frame out of the car would allow me to do the job on a workbench at a comfortable height. If I ran into a snag I could better cope with and solve the issue easier if not working with my hands over my head.
So I pull the left rear sub-frame bolt out and all is going well. Then I get to the right rear. Impact wrench is spinning but nothings happening...Grrr sh*....
continued with next pic
10-14-2004, 07:01 PM
#2
AudiWorld Super User
Thread Starter
Doncha just hate surprises!?!
<center><img src="http://pictureposter.audiworld.com/711/artmi2.jpg"></center><p>
Wouldnt ya know it... the rught rear sub-brame bolt was either stripped or it's welded nut had broken free of its spot welds. Had to be a manufacturing problem as sub-frame has never been removed as was evidenced by the yellow tamper-resistant paint still in place and un-broken on the sub-frame bolts.
Only one course of action... surgery. DEEP surgery!
The metal at this particular spot is tough as well it should be. This is a structural section of the uni-body. The steel here is probably 3/16"-1/4" thick. Once I got a flap cut it was still a bear just folding it back and laying it away so I could get to the Mot*%r F(#k$r. I was hopppin mad at this point. I had planned on a two hour cake-walk and I was just passing that point and nothing had been accomplihed other than right rear sub-frame bolt removed.
This pis shows the square bolt and cage that sits over it. That bolt is "free-floating within that cage and the cage is the guilty party in my case. Its a 3-sided piece but only two sides get a tiny spot weld where the contact the floor withing the square uni-body tube. One of those had a tiny bit of weld on it and the other had been totally/completely missed by the welder. It took an original tightening from the factory but just couldnt take a single removal without breaking free.
So rather than just weld the stock square nuts back in I decide to do it really right. Off I go home so I can machine not 1 but 2 pieces of 2"x2"x1" thick tool steel nuts to weld in to that spot on BOTH rear subframe mounts. Turns out the left rear had been spot welded in 2 places as it should've been but I wasnt taking any chances at that point. It "may" have worked for centuries. Now they both WILL work for centuries!
Five hours later I finish welding the new tool steel nuts in place and cant bend the flap I was so careful to make without distorting it. So I do the best I can do. But thats for the next pic...
to be continued again...
Wouldnt ya know it... the rught rear sub-brame bolt was either stripped or it's welded nut had broken free of its spot welds. Had to be a manufacturing problem as sub-frame has never been removed as was evidenced by the yellow tamper-resistant paint still in place and un-broken on the sub-frame bolts.
Only one course of action... surgery. DEEP surgery!
The metal at this particular spot is tough as well it should be. This is a structural section of the uni-body. The steel here is probably 3/16"-1/4" thick. Once I got a flap cut it was still a bear just folding it back and laying it away so I could get to the Mot*%r F(#k$r. I was hopppin mad at this point. I had planned on a two hour cake-walk and I was just passing that point and nothing had been accomplihed other than right rear sub-frame bolt removed.
This pis shows the square bolt and cage that sits over it. That bolt is "free-floating within that cage and the cage is the guilty party in my case. Its a 3-sided piece but only two sides get a tiny spot weld where the contact the floor withing the square uni-body tube. One of those had a tiny bit of weld on it and the other had been totally/completely missed by the welder. It took an original tightening from the factory but just couldnt take a single removal without breaking free.
So rather than just weld the stock square nuts back in I decide to do it really right. Off I go home so I can machine not 1 but 2 pieces of 2"x2"x1" thick tool steel nuts to weld in to that spot on BOTH rear subframe mounts. Turns out the left rear had been spot welded in 2 places as it should've been but I wasnt taking any chances at that point. It "may" have worked for centuries. Now they both WILL work for centuries!
Five hours later I finish welding the new tool steel nuts in place and cant bend the flap I was so careful to make without distorting it. So I do the best I can do. But thats for the next pic...
to be continued again...
10-14-2004, 07:12 PM
#3
AudiWorld Super User
Thread Starter
6th hour and I can finally get back to the task at hand... allroad tranny mount conversion
<center><img src="http://pictureposter.audiworld.com/711/artmi3.jpg"></center><p>After getting super heavy-duty left/right rear subframe nuts welded in I realized I could not conform the "flap" back into the hole I had cut and just weld it into place. I had to cut some 1/4" steel plate "patches" to weld over and seal the compartment that houses the sub-frame nuts. I dont want water, dirt, dust and debris getting into that channel. Only way was "patch-work." I didnt have the Laser Red Aerosol paint with me so I used some Krylon just to prevent rust til tomorrow morning when I can go back in and re-paint this the color of the car. ICK... makes me shudder looking at this.
I never got the sub-frame out or the Delrin bushings installed as I was approaching almost 5x the time I allowed for this.
But now that I've made you guys suffer about 1/10,000 of my pain I'll get to what you really wanna hear.
Hint: You'll like it!
I never got the sub-frame out or the Delrin bushings installed as I was approaching almost 5x the time I allowed for this.
But now that I've made you guys suffer about 1/10,000 of my pain I'll get to what you really wanna hear.
Hint: You'll like it!
10-14-2004, 07:28 PM
#4
AudiWorld Super User
Thread Starter
First off I have to say this didnt work out exactly as planned either...
<center><img src="http://pictureposter.audiworld.com/711/artmi4.jpg"></center><p>
but it was easy to make it work.
If you check my previous pics of the Allroad mounts you'll see a Kevlar cable running around it just under the top cap. I "thought" that cable was to prevent the mount from hyper-extending. I was wrong. Its nothing near as complicated as that. It simply holds the cap on during installation. Nothing more. Silly me, always trying to make it more complicated than it need be.
But in our case (B4/B5) we hve to cut it. We cant install the mount in one piece as it wont fit thru our center cut-out in the sub-frame. Use heavy scissors that are "sharp" or aircraft tin snips. It's not hard but it's "stingy" with a fibrous inner weave that has a gazillion strands of what looks like fiberglass. Yellow in color and hard to cut because its so fine... finer than the hair on your head.
The dust boot may or may not be useable on ours as well. But we have a more pronounced "shroud" of metal than the vehicles these cars are designed for so we're likely ok. I do remember not being able to use that boot when I went to B5 mounts on the 90 so it "may" only be the 90's that cant use the dust boot and the B5's can. You guys will discover that and report as soon as someone else does this.
Other than those items it's a very straight-forward install. Just place the AR (allroad) mount up into the sub-frame bracket then place the cap on top of the bracket. Locate the two pins in the top of the lower mount into the corresponding holes in tha cap and install/tighten the 3 mounting bolts in each mount.
Only item everyone will need regardless of if they are B4/B5 chassis is a new, shorter center bolt for each mount (2 total). The spec and size needed is 10Mx1.5mmx35mm length, grade 8.8.
Driving impressions to follow...
but it was easy to make it work.
If you check my previous pics of the Allroad mounts you'll see a Kevlar cable running around it just under the top cap. I "thought" that cable was to prevent the mount from hyper-extending. I was wrong. Its nothing near as complicated as that. It simply holds the cap on during installation. Nothing more. Silly me, always trying to make it more complicated than it need be.
But in our case (B4/B5) we hve to cut it. We cant install the mount in one piece as it wont fit thru our center cut-out in the sub-frame. Use heavy scissors that are "sharp" or aircraft tin snips. It's not hard but it's "stingy" with a fibrous inner weave that has a gazillion strands of what looks like fiberglass. Yellow in color and hard to cut because its so fine... finer than the hair on your head.
The dust boot may or may not be useable on ours as well. But we have a more pronounced "shroud" of metal than the vehicles these cars are designed for so we're likely ok. I do remember not being able to use that boot when I went to B5 mounts on the 90 so it "may" only be the 90's that cant use the dust boot and the B5's can. You guys will discover that and report as soon as someone else does this.
Other than those items it's a very straight-forward install. Just place the AR (allroad) mount up into the sub-frame bracket then place the cap on top of the bracket. Locate the two pins in the top of the lower mount into the corresponding holes in tha cap and install/tighten the 3 mounting bolts in each mount.
Only item everyone will need regardless of if they are B4/B5 chassis is a new, shorter center bolt for each mount (2 total). The spec and size needed is 10Mx1.5mmx35mm length, grade 8.8.
Driving impressions to follow...
10-14-2004, 07:32 PM
#5
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that happen to me this summer at work, SUX BIG TIME...Hint inside
now yes i am 20 yrs old this is just something constructive, but we used a "hole" saw blade, the type you use on doors. And for the end we put a gromet in the hole, looked like stock. HOwever since you wanted to weld in the new nut, (insert chiwowa (sp) quote), i guess that was is much better.
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10-14-2004, 07:36 PM
#8
Thanks for the write-up. Sorry to hear about your trouble but, as always, you made it better!
Luckily you have the means to do so. If that happened to me, I'd be screwed.
Looks like this will be my next mod (I was already planning on replacing the mounts anyway). Thanks!
Looks like this will be my next mod (I was already planning on replacing the mounts anyway). Thanks!
10-14-2004, 07:41 PM
#9
AudiWorld Super User
Thread Starter
Allroad transmission mount conversion driving impressions...
On this one I got something right. It is incredibly good. The thing I couldnt tell and didnt know just by looking at the mounts when they were out of the car is how this mount actually fits against the steel sub-frame housing it fits in that neither the B4/B5 mounts have. This mount has a rubber layer between it and the mount plate it's bolted to further diminishing vibrations and resonances.
Its very quiet and takes mucho slop out of the system that even a new stock OEM mount has an abundance of. It's discernably better, tighter and far far smoother. I drove all the way home with my hand on the shifter and the difference is quite startling. Couple with my snub mount this is a KILLER combination! And speaking of the snub I think it will be a good idea to take a peek at my snub tomorrow to check that it's still centered within its housing. I measured and "eye-balled" the mounts prior to installation and they were within 1/16" (.0625") of each other height-wise but that much deflection at the tranny could be double that or more at the engine front. Couldnt hurt to take a peek. And even if mine turns out to be perfectly centered it doesnt mean yours will be. This is something everyone should do after this conversion. This would be a logical "part" of this conversion. I know the B5 snub is a harder/more complicated install than the the B4 cars. But the snub housing is the part the snub sits in and hits against when taking up driveline slack. Its fretfully easy to adjust and re-center if necessary on both cars. Less than 30 seconds to check and 3 minutes to correct. Dont guess, DO IT!
Would I do it again knowing what I know now? Betcher *** but I wouldnt be in as big a hurry to drop the sub-frame ;-)
Its very quiet and takes mucho slop out of the system that even a new stock OEM mount has an abundance of. It's discernably better, tighter and far far smoother. I drove all the way home with my hand on the shifter and the difference is quite startling. Couple with my snub mount this is a KILLER combination! And speaking of the snub I think it will be a good idea to take a peek at my snub tomorrow to check that it's still centered within its housing. I measured and "eye-balled" the mounts prior to installation and they were within 1/16" (.0625") of each other height-wise but that much deflection at the tranny could be double that or more at the engine front. Couldnt hurt to take a peek. And even if mine turns out to be perfectly centered it doesnt mean yours will be. This is something everyone should do after this conversion. This would be a logical "part" of this conversion. I know the B5 snub is a harder/more complicated install than the the B4 cars. But the snub housing is the part the snub sits in and hits against when taking up driveline slack. Its fretfully easy to adjust and re-center if necessary on both cars. Less than 30 seconds to check and 3 minutes to correct. Dont guess, DO IT!
Would I do it again knowing what I know now? Betcher *** but I wouldnt be in as big a hurry to drop the sub-frame ;-)
10-14-2004, 08:10 PM
#10
AudiWorld Super User
Thread Starter
Very clever idea! Because I wanted to use HUGE new machined tool steel nuts...
I needed a good size hole tho it looks bigger in the pics than it really is (approx 2.75"Hx3.5"W). But because that area is "structural" and not just sheet metal I had to make it stronger than before it was cut.
But I'll give it to ya on one thing... it did sucketh! My UrS4 did the same thing on the same side once but its a different system altogether and has another rubber bushing up in that area with a steel threaded insert cast into the rubber bushing body. It was a piece of cake to replace that bushing and bolt compared to this.
I'll probably do the same thing at the front end when I get back to those control arms and the Delrin bushings project. At least that spot will never be seen so the "scar" will be a LOT less obvious.
But I'll give it to ya on one thing... it did sucketh! My UrS4 did the same thing on the same side once but its a different system altogether and has another rubber bushing up in that area with a steel threaded insert cast into the rubber bushing body. It was a piece of cake to replace that bushing and bolt compared to this.
I'll probably do the same thing at the front end when I get back to those control arms and the Delrin bushings project. At least that spot will never be seen so the "scar" will be a LOT less obvious.