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Hi Art.
The 740/940 windshield wiper motors are fortunately not the same and are much more reliable than those used in the 140s/240s. The latter were of course famously prone to failure from rusty/loose magnets on the inside motor casing, which for the benefit of others can usually be repaired successfully by disassembling the motor, removing the armature, thorough rust removal and epoxying them back in place, careful when reassembling the cam gear and contacts.
The main problem with the 740/940 wiper systems, both front and to a lesser extent the rear, can be extremely slow operation, most noticeable at low speed when dry wiping or trying to clean road spray off the window. As noted in the FAQ, it's caused by the wiper shaft bushing lubrication drying out. Ensuing aluminum corrosion can make them one step short of frozen. Caught early, external lubrication can temporarily help, but the proper fix is to remove the shafts, polish up everything and re-lubricate with a quality all-weather grease, such as marine grease used for drive shafts.
As long as I'm on the topic and for the benefit of others who might later follow this discussion, I'll add the following wiper related tips as there is no longer a mechanism to add information to the FAQ.
Access to the front wiper system is much simpler than the 240s where you often end up having to crawl under the dash. In 740s/940s, the windshield wiper system is under the cowling below the windshield. Cowling removal is a fender bolt on either side at the front, hidden middle bolt under the rubber strip, lift front edge and slide forward off the pins on either side at the rear, be extra careful not to scratch paint (use a blanket). While you're at it, it's a good time to fix those problematic loose leaf screens using a heat gun on low and pressing the mesh back into the mastic with the edge of a blade, smoothing over the oozed mastic to properly hold it in place like the factory should have done in the first place.
The tailgate wiper motors are also quite reliable. Access to the tailgate wiper system requires removal of the inside door panel trying not to break the slightly delicate plastic clips, including the looped tabs along the bottom edge and the inner clip frames at the top. Getting the bezel over the T-handle is often problematic as the plastic handle cover is often very difficult to remove -sometimes simpler to just split the bezel in the middle and re-glue it afterwards with mastic or whatever. Lift the panel out a bit at the bottom then push straight up. Careful when aligning the clips on reassembly. There is a repair kit if the top clips get broken. To the best of my recollection, those motors are also different from the 140/240s, definitely the assemblies are. Main problem I have with 740/940 tailgate wipers is the aluminum mounting shaft through the tailgate eventually becoming loose -when the shaft starts to becomes loose the aluminum threads easily get worn and when you go to give it a good tighten (tricky to get a wrench between the glass, best to use a large deep socket) the threads easily strip, I've had to use spacer washers to get the nut back out onto good thread -I'm thinking about trying thread locker next time, next step after that will be epoxy.
I don't have headlight wipers, so I can't attest to the reliability of those motors.
I'm glad this post came along as it reminds me I've got one 940 in definite need of wiper lubrication before the fall rains arrive
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now
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