A4LD pikaopas korjaukseen

[Pappacosworth]

Seuraavasta osoitteesta http://www.geocities.com/MotorCity/Flats/3349/a4ld.htm
vain copypastesin

THOUGHTS ON THE A4LD OVERHAUL

The A4LD is not really a bad transmission to work on. It is really fairly easy, but attention needs to be placed on a few common trouble spots. Before tearing it down make sure you keep the two band servo assemblies and springs seperate, and do not mix them up. These are the front overdrive band, and the center intermediate bands. Another tip is do not disassemble the pump, which is part of the bellhousing, unless you have the alignment tool. Misalignment here spells almost instantanious failure. Basically, I will assume the tranny is all torn down, cleaned, and ready to inspect. The first think is that anytime the A4LD is overhauled, replace the thrust washers. I get most of my parts thru a place in Indiana called National Auto Lines. They have most of the parts you will need at very reasonable prices. The first area to inspect is the tranny case. Look in the rear where the governor hub goes, and look for wear grooves in the case. If no wear is noted, use the rubber square cut seal rings for the governor. If wear is noted, stick with the steel rings. I usually take some fine emmory cloth and polish the bore to lessen the wear. Next ares for inspection is the governor itself. Make sure the valves in the governor assembly move freely, they cannot stick even a little, unless you like torture. If they stick, clean them and polish the valves with fine polishing cloth. The next area is inside the case, look at the rear one way clutch hub, and inspect it for scoreing, and check the rollers in it, make sure no wear is evident, and that all rollers are in place. Next look at the rear band. This is the low/reverse band. It will likely look good, they hold up pretty well, but check it just to be safe. Next check out the center band. This is the intermediate band, and is the same part number as the front band, the overdrive band. They are seldom reuseable, in fact the C-4 band may be able to be used, but I wouldn't guarentee this. The C-4 band can be gotten with hiperformance material, and would be a really good improvement for the A4LD. Be sure and soak the replacement bands in a bucket of tranny fluid for at least an hour prior to installing them, and the same for the clutches. Note that there are differences in the clutch disks, in regard to the inner splines, and this is the key to know which clutches are which.When you start the reassembly, the rear band will sometimes rotate out of position, so save yourself some grief, place the band in position, then install the rear band apply piston loosely to help hold it in place. To reassemble the rear half of tranny, that is the parts from the center support to the rear sun shell drum, reassemble the parts on a bench, then slide the assembly into the tranny, because assembling it piece by piece in the case is a nightmare, and if the stackup is not right will lock up or damage the rear half. I use two coathangers shaped like hooks to wrap around the sun shell gear, to lower it into the tranny, then pull them out. Next, is the middle band and struts. This part requires a steady hand. Next is the most critical part, and is where most mechanics mess the tranny up, leading to a quick failure. The center support. Inspect the rear inside bore for wear from sealing rings. If it is worn, replace it. A tranny machine shop in Arizona sells them sleeved, and if they are worn and reused, high gear fails soon after rebuild. Install the viton square cut seals marked specifically for the center support, coat them with a healthe dose of petrolium jelly, and slip it into the fromt clutch drum being carefull not to cut the seals. Another tip is to then place this into the freezer for a half hour or so. After the half hour the seals hold shape, and should slide into place. Take the input shaft, install it into the splines in the hub that you already installed, then set the center support into place, but do not force it. Wiggle the input shaft easily and the support will slowly fall into place with only its own weight. Assemble the rest of the tranny, inspecting the front overdrive planetary gear set for wear, and note that the oneway roller clutch holds in one direction, and turns in the other. Inspect this for scoreing also. Continue reassembly, and when it is together, except the valve body, inspect the valve body for sticking valves, or debris. If any debris is noted, completely dissassemble it and clean it, making sure all valves will move by their own weight. Caution tho, due to many valves, springs, etc, be extremely careful not to lose them or mix them up. I would also like to advise you to install the A4LD-JR shift kit by TransGo, also sold by National Auto Lines. Sticking valves in the valve body are one common cause for failure. Also both bands adjust in til snug, then back out 2 turns, except the 4.0L, the front backs out 3 1/2 turns, and the center backs out 2 turns. The vachum modulator is non adjustable from the factory, so a adjustable replacement is advised. Be careful not to loose the plunger behind the modulator. This isn't intended to be a complete guide, I am assuming you have some experience here. I strongly advise buying a manual from ATSG (Automatic Trans Service Group) available from National also. They are a very good guide, for diognostics, adjustments, and specs. A few places are offering rebuilt overdrive planetary gear sets, and a couple places strengthen theirs. This is a weak link, so consider getting one. I will research more on the supplier for parts, and post links here soon.If any metal debris was found in the pan, I'd also recommend replacing the convertor, and flushing the tranny cooler and lines. This is another area people fail to do, resulting in a short life.

TRANNY LINKS

NATIONAL AUTO LINES 1-800-428-4300 For all types of engine, and tranny parts mailed to you.

TRANSMISSION EXCHANGE Supplier of recon trannys, parts, and shift kits.

ARIZONA TRANSMISSION MACHINE Supplies several reconditioned components

TRANSTECSupplier of tranny kits, and components

TRANSTAR INDUSTRIESSupplier of tranny parts.

For strengthened od planetary sets e-mail ACESIMI@AOL>COM and ask for part number FBA22 (A4LD OD planetary set).