hi,
i have a aw71 with about 241k miles 94 940, on a trip back in texas, where the internet speeds are 75 mph, i sped at 85-90 mph for at least 100 miles, also, did the same couple of days earlier on the way to my destination.

mobil 1 fluid had about 25k miles.

tranny 4th gear failed after i pulled over for a short stop home.

got a tranny green book, which states these problems:
1. dirt in the governer
2. shift valve 3-4 sticking (in valve body)
3. b0 brakes fault (the overdrive part in tranny)

i replace od switch and relay, each original, replacements work, i can hear them clicking.
i just flushed the tranny with new fluid, no effect.
i doubt dirt is in the governor and the shift valve is sticking.

leaves to overdrive in tranny.

thoughts:
1.
od part is in the front section of tranny bell housing and complete disassembly of tranny not necessary.

i've never worked on a tranny other than oil seal, tail bushing and orings, but i can tackle almost all other projects.

i thought about diassembling the tranny to the od part and replacing the friction pack (3 of them) and reassembling it.

cost: friction packs can be found on ebay for about $50, rabestos or sourced other places

bottom line:
gain experience at rebuilding part of tranny, save bucks, no worry about sourcing another tranny, getting harder to find in houston.

can work on any other tranny in my 3 cars later, too.

drawback:
need any special tools, such as extractor for tranny oil pump?
have instructions, but never worked on tranny.

2.
easiest way is to swap trannies, which i've done before.
i got a spare, 92 aw70 tranny, which could be cleaned up, orings, seal, tail bushing replaced.

buy another aw71 tranny, but shpg included cost $350-550. i can possibly find another aw71 tranny in area, houston, austin, etc. and get it for about
$150-200, maybe.

car runs very well, interior very good, a lot of new parts and upgrades, worth keeping.

all help and advice on trannies much appreciated,

thanks again,
byron golden
86 245
92 245
94 940

If you want to have 4th gear work all the time you can order a bypass plate from IPD that allows fluid to flow like it does in normal operation. You can also modify your old solenoid by opening a flow path between the two passages and use just the outer o ring. A dremel works just fine. Leave the wire disconnected and be all set. It is nice to have things work like they should but if you never kick the overdrive out then why not bypass it. larry

before i did anything else i would

1. verify the wire from the od solenoid to the shifter is intact and not broken
2 if the wire is intact i would seriously think you have an od solenoid problem

it is unlikely you suddenly developed internal transmission problem with 4th gear.


in your case if it is a bad solenoid the second most likely cause...1rst being wire use a 1/4 drive FLEX head ratchet with a 12mm socket to loosen the 2 bolts.

this is the safest and easiest way to gain access to those awkward bolts

ted,
thanks. i was just thinking that maybe the two shift bushings missing may be mis-positioning the gear.

i ordered the bushings and will try again, and will tighten the kickdown cable, but it looks about correct. i tightened it once.

it'll be a few days before the bushings arrive.

regards,
byron

hi ted,
thanks for your reply.

ok good to hear about rare 4th gear failures.

i did replace the od solenoid with a new one, checked the old one, 12V, good, resistance, good. so i'm keeping my old one.

surprisingly, when i looked at the linkage, both bushings are gone, but i presume they've been gone a while, so i don't think that was a problem.

i'll replace them and then check.

i tightened a bit my kickdown cable, but that shouldn't cause a 4th gear problem.

i'll recheck issues external to the tranny.

one check is to unscrew the solenoid and turn on the engine to try to push any dirt that may be causing blockage in the port to the solenoid.

i hope it is a simple issue.

thanks,
byron

a mis-adjusted kickdown cable can make 4th very hard to get into as you accelerate.

3rd gear will hang forever without dropping into 4th

seen it and done it