Owners typically report a "clicking" noise (or worse) from the area of the transfer case upon acceleration or sometimes when making a tight low-speed turn. Fortunately for me at least, I have not had the "benefit" of experiencing this on my '88, so I am reporting all of this from second-hand information. But it seems like once a month or so I get an e-mail from one of the 600 members of the iX Registry or from someone who has "gotten religion" and wants to join us because of a drivetrain problem.
Based on these reports and previous iXchange articles, I believe most of these failures are due to stripped splines on the front driveshaft. Yes, another souce of problems is a stretched chain in the transfer case which slaps internally on the inner baffle (oil baffle) of the transfer case. And front CV joints and the front differential are also possible sources of grief, but if you suspect a similar problem, look to the splines first. As you would anticipate these failures can result in very expensive repair bills. If the Xfer case and driveshaft are ruined, the "easy" but most expensive solution is to buy a rebuilt Xfer case and front driveshaft from BMW. On the other end of the cost spectrum, it may be sufficient to replace (or possibly repair) the front driveshaft if the Xfer case gears are not damaged -- see previous articles in the iXchange newsletters #18 and #25.
The driveshaft extends into the transfer case gear only by about 3/4 inch, even though the splines on the gear in the transfer case are 2 inches wide. By inserting shim washers in the driveshaft to force it into the transfer case by about 3/8 inch or so, the contact area is increased by 50%.
So here is the procedure:
1) Buy and/or assemble the hardware you'll need:
2) Apply the handbrake and put the transmission in neutral. Chock a wheel on the right side. Jack up the driver's side of the car, jacking on the frame rail under the car next to the transmission tunnel. Leave the wheels on -- you should be able to turn the driveshaft to access bolts by turning the left front wheel by hand.
- 3 hardened (10.9) 50mm M10 fine thread bolts
- 3 nuts for these bolts
- 3 lock washers for these bolts
- 15 small-diameter washers (hardened, if possible) for these bolts to be used as shims (1-3 for shims on each bolt, combined about 3/8 inch thick, 3 spares, 3 under the bolt head if there is clearance.) You may need to file the edge of the shim washers to square off a portion of the circular edge so that they seat properly -- see below.
- 1 tube of blue Locktite
- 17mm combination (open/closed end) wrench
- 17mm socket and ratchet
- Torque wrench (torque to about 50 lb-ft for 10.9 hardness bolts, 35 lb-ft for 8.8 bolts)
- Large screwdriver
- 1 new guibo (optional, but might as well) -- Part # 26 20 1 701 094
- Spare plastic cap (for the driveshaft at the Xfer case) if you are going to check the lube on the splines
- Floor jack or your iX's crank jack
- Wheel chock
- 2 jack stands
3) Place jack stands under the frame rail in the front and under the crossbrace at the rear. Leave the jack in place as an extra precaution.
4) Note the arrowheads around the circumfrence of the rubber guibo. The arrowheads should point toward the flange arms. If you are going to replace the guibo, be sure that the arrowheads point toward the flange arms on the mating part. Important: Only tighten nuts or bolts on flage tab whenever possible to reduce stress in the guibo.)
5) Remove the 3 bolts and nuts that hold the front driveshaft, centering flange, guibo and front differential flange together. (Rotate the driveshaft so you can access the bolts by rotating the left front wheel.)
6) Insert a large screwdriver between the driveshaft and the back side of the flange. Pry the driveshaft backward toward and farther into the transfer case. You should be able to open up the gap by a half inch (pry it back just enough so you'll be able to insert 2 washers, about 3/8 inch.)
6a) Or remove the driveshaft at this point (see iXchange #18) to check the lubrication on the splines (use Moly grease or Anti-seize)
7) Remove the old guibo and centering flange part. Insert the centering flange part into the new guibo and install them against the front differential flanges and bolts. Make sure when you install the guibo, that the arrows on the guibo point to flanges and bolt heads (rather than to nuts.)
8) Put a washer on each bolt and insert one new bolt through a driveshaft flange hole. Insert 2 shim washers on each bolt between the driveshaft flange and the centering flange. Check that these washers seat properly -- depending on how large the washers are, you may need to file one side of the washers to allow them to seat properly.
9) Apply some blue Locktite and complete the assembly of washer and locknut on this bolt. Then "loosely" tighten the nut to draw up the driveshaft and enough so that you can turn the driveshaft (by turning the front wheel) without the bolt or nut hitting the case of the front differential or oil pan. Re-shim and/or remove the washer under the bolt head if necessary.
10) Repeat step 8) for the remaining 2 bolts. Rotate the driveshaft through several rotations to confirm that nothing binds and that eveything seems OK.
11) Hold the nuts with the combination wrench and tighten the bolts with the torque wrench to about 50 lb-ft. for 10.9 hardness bolts.
12) Lower the car. Put it in, say 3rd gear and push it forward, listening for any scraping or binding.
13) Turn off the radio and blower fan and drive the car slowly for 30-40 feet, again listening for any strange sounds.
14) Jack the car up and look for any evidence of scraping against the transfer case or elsewhere around the guibo.
15) If all looks good, drive the car for a week or so, then re-check that all is OK.
Hopefully this will significantly extend the life of the splines on the driveshaft and transfer case gear. And, please let me know your iXperiences with this modification.
On July 7, while cruising across Western Wisconsin to my parent's retirement property I suddenly heard a terrible screeching/ howling / whining sound over the volume of the radio. I immediately pulled off the road as fast as the brakes would pull me down; my first thought was the blower-fan bearings had finally given up (they'd been chirping loudly on and off for the last few months.) The noise stopped when I did, though, so I attempted to pull out on the road again. The screech began again as soon as the clutch was released, the car didn't move and a quick lean under the car from the driver's seat confirmed the sound was from the transfer case, although I couldn't tell exactly what the problem was.
Having read the other Registry articles, I knew well enough not to tow the car but instead called for a flat bed; $300 and 70 miles later the car was back home awaiting further investigation. At this point I was completely disgusted with the car and since I had multiple other home improvement projects pending at the time, I let it sit for a few days. I cooled off a bit and read all the registry articles on transfer case problems.
When I finally pulled the front shaft a few days later, I discovered (as apparently many others have) a stripped shaft spline, dry and rusty from not being properly lubricated. However, unlike some others, I also had some lesser damage to the hardened steel inner spline on the transfer case. There was no way I could just replace the shaft with a new unit and have any reliability, since it would only be a short matter of time before the new shaft spun too. Having just spent $1000 on control arms, tie rods and a new half-shaft in April and with the wife six-months pregnant, there was no way I could justify the $2400 for a new case and shaft, even if I did the labor myself. Heck, there was no way I could justify ANY additional expense; thus began my search for an alternate (read: cheap) solution to get the car back on the road in a reliable state.
Examining the case and shaft, there is 2 5/8 inches of depth to the interior spline on the case, but only 1 _ inch spline on the shaft; of this, only 3/4 inch actually meshes. This design is obviously intended to allow the shaft to slide into the case for easy removal from the car. Other members have documented adding some extra spline to the length of the shaft, but that was not going to be sufficient for my situation. I went back and forth with Gordon, Alan Alfano and David Ritter via email, and finally decided my best alternative was to have a custom shaft made which would utilize more of the depth available in the case, albeit at the cost of easy removal of the shaft. I was going to have to remove the transfer case in order to insert the shaft, but I figured either way the case was going to have to come out - if this didn't work, I'd need to repair the damaged pieces or install a used unit anyway.
I made contact with a local machinist named Jesse Frandrup through a mutual friend; he runs his own machine shop on the side, and agreed to take on the project when no one else would. He decided to use my old shaft, cutting the damaged spline end off and making a new spline with a length of 2 inches even. He felt it would be better to leave some room for the shaft to move within the case if needed, and this would still double the amount of spline meshing. Also, we agreed since the original shaft was not heat-treated that this one shouldn't be either, and his experience told him there would be no need to rebalance the shaft when done. Two weeks later, he had the shaft completed. As you can see from the photos, it added significantly to the length. He used T4140 steel, which he advised should be a good quality material even though not heat-treated. Price was $285, almost to the penny what a new standard shaft would have cost.
While I was waiting for the shaft to be done, I had dropped the transfer case and related items. Transfer case removal is well documented in the Chilton's manual, and it only took about 2 _ hours (really!) to pull the exhaust, rear driveshaft and drop the unit. Upon inspection, it appears someone worked on the case previously, as it had a fresh gasket poking through the two halves of the unit. I was not interested in pulling it apart personally, but was somewhat encouraged by this, so I just cleaned up the outside of the case.
Since this was to be a once-in-a-lifetime project, I (belatedly) decided to replace every "consumable" part under the car. I had to wait a couple weeks for Guibos, bolts and shifter parts to come from Maximillian Imports via Germany before I could start reassembly. By the way, a plug for these guys - Shane at Max was superb, emailing me several times daily at one point and long-distance faxing diagrams to me several times to help me decide which way to go. Everything finally came in, and five weeks (!) after the initial breakdown I began reassembly.
What took 2 _ hours to remove took about 15 hours to reinstall, but I took my time and was working in my backyard, on my back, in the rain (all the money designated for completing my garage this year ended up in the cars...). In order for this to work, the shaft had to be inserted into the case while out of the car, along with the guibo and centering pin attached, and then the entire assembly raised into place. I used molybdenum grease on the spline as recommended. The shaft was a snug fit in the case, and the last _ inch required gentle tapping to seat completely. I measured the exact distance it should be inserted by comparing with the old shaft piece. I replaced all the worn shifter parts first (almost worth the effort of removing the case just for this repair - a huge improvement). The rest was simply a lot of muscle work and time to put pieces back where they belonged; about 4 hours was spent replacing the muffler, since it required a cutting torch to remove the old bolts from their flanges.
Due to another unrelated problem, I've only gotten about 100 miles on the car to test it at this point, but there are no unexpected vibrations or noises, nor any leaks. The front guibo does not appear stressed, and the car drives fine. All told, it cost me $1125, including: Flatbed towing from the middle of nowhere; new muffler; shifter repair kit; rebuilt shaft; all new hardware/ guibos/ etc. If you forego all the extra items, the job could be completed for around $300.
Thoughts and Impressions
1) Don't buy an undocumented iX, it just isn't worth it. The only documentation I have on the car is for a clutch replacement the day before I bought it and a new half-shaft on the driver's side. I fell in love (lust?) with the car though as soon as I saw it, and as a result I have about $3000.00 in repairs in the last 12 months, all labor done by me. By the way, none of the items that have been replaced were noted by the local dealer on inspection.
2) Check the front driveshaft. Check it often. It's a two-hour job max from start to finish, very easy. Much easier than repairing it.
3) This is definitely not for everyone, but it does work. For me personally it was an excellent solution, since I had my 86 325e to drive while the iX was down, I could do all the work myself, fix some other items in need of repair, and it got my machine back on the road for less cash. It may also be useful for others looking to beef up their driveline for performance applications. My machinist kept all the specs for this operation and is willing to assist others, but realize that it takes about 2 weeks for him to do the job and he needs your (or someone else's) old shaft.
Frustrations aside, this process was a huge opportunity to interact with some great people, who selflessly gave up time and expertise to help me through this. Thanks to Alan, David, Shane, Jesse and especially Gordon, without whom we would not have access to this wealth of information.
Happy iXing! -- Sean
NOTE: Dave Ritter of Marquette, MI extended his driveshaft several years ago and reports no problems. The mechanic that did this work is John at (248) 760-3353 or e-mail, firstname.lastname@example.org. Dave says, "John has made special arrangements to have these things made, and requires your old driveshaft as a core. You could discuss with him your specific needs. John is very experienced with these cars."
We did finally settle on the car, but it was a real PAIN! The first offer our insurance company gave us was for a 5spd 325i with cloth seats. The totaled iX was an automatic with leather. And, we had sent them 5-6 printouts of similar cars from Autotrader.com, averaging $8,500.-$12,900! So then they came back with an offer of $7,600. Still no good.
So we called the vice-pres. of claims and told them we couldn't replace her car for $7,600, much less the expense of traveling to find one. So we finally settled for $9,300.. And we got to keep her old car,which was $1,200. So we got a check for $8,100. The way they came about the $1,200 was by calling one of their salvage yard guys telling them what they had and they made our insurance company an offer of $1,200. If we didn't want to buy it back, they would put the car in a "salvage pool" and take bids. If no one offered them as much as $1,200, then the frst guy is obligated to buy it for $1,200. So they were guaranteed $1,200.
We also learned that the salvage yard guy called the insurance company back to see what happened with the car and was going to make a higher offer after he found out how rare those cars are and how good the condition of her car was. I thought that was funny! SO -- you might want to make sure to check your insurance policy to see if you would get a fair price in case your car were to be accidently totaled. I switched to an insurance company that offered a "stated value" policy for my ///M3. When we find another car we are going to do the same with the new car. That way, if this were to happen again, they would just cut us a check for the appraised value of the car. The insurance company that we have now is "Progressive." It's exspensive, but after all of this., it might just be worth it!
I've added a photo in the photo archives showing the drain and fill plug.
Jack the motor after undoing the right motor mount. Then use a 24MM deep socket ground to be thinner and shorter than normal.
He also advises us to cut a hole in the boot on the connector to prevent oil from backing up the wiring and running out elsewhere.
If you're replacing the clutch on your 325iX, make sure you're getting the true "iX" pressure plate. All of the warehouse distributors I've spoken with are now selling the regular 325i pressure plate to
325iX customers. BMW still sells the unique plate for these cars (21211225883). Also, remember to replace the (nylon) pivot pin and grade12.9 pressure plate bolts when you do your clutch replacement.
I recently had a fuel delivery problem that destroyed a fuel pump. Apparently water was in my tank and eventually the Mahle filter collected enough to freeze solid and wouldnt pass more fuel through. I had just changed the filter 4 months before and suspected a faulty fuel pump until I investigated further. We discovered that a plugged fuel filter will quickly destroy a fuel pump so change frequently!! The most interesting thing however is that I put on a Hastings brand (which is more expensive) and the car lost a hard to start characteristic!!
Also, I came across Shelby Omni GLH 2.2 motor in nice condition with a nice 4-bolt set of 15" alloy (swiss cheese tyle) OEM wheels with 4 new Dunlop 195x60 winter tires and on a whim tried them on the '89 iX. Was I surprized to find that they fit perfectly, and dont even look too bad. The centers were even concentric to the iX hub.. I used the iX wheel lug bolts and the taper is similar. The wheel offset appears good, although I didnt measure it. Height was within 3/8" of the worn 205x60x15 I took off. They clear the brakes and run fine to high speed.. Possibly other more common FWD Chrysler 15" wheels would also work and should be very reasonable used.
Zygmunt was also the cheapest on Bilstein HD's for the iX. $101 ea for the front and $72 for the rear, with free shipping. Their control arms were also the cheapest at $139 each with free shipping.
Click on links to select year (1988 - 1991), then manufacturer (BMW), then model (BMW 325iX AWD (E30)) and engine (6-2494cc 2.5L SOHC (M20)).