Can an experienced wrench replace 5 speed 5th/rev synchro

[macx]

Main thing I'd need to know is if there are any specialty tools really required -

just want to replace the 5th / reverse synchro - won't stay in reverse even with mild throttle.

I've found an online manual, but manuals often get very involved with steps that maybe can be skipped if not doing a complete rebuild but just fixing one specific thing.

Gotta pull the trans for a leaky rear main & replacing the slave & clutch while I'm at it.

Not going to put a lot of miles on this rig, and it only has 75k on it now, so hopefully replacing just that synchro can be done without other stuff needing replacing.

Seems I read part of a post on here about doing this but can't find it now.

Thanks for any info!

 

[adsm08]

The syncros in that tranny are pretty easy to replace. If you have ever taken an manual apart before you should be ok.

 

[macx]

Yeah, have been into Chev Rock Crushers (425 hp big block Camaro), Mopar hemi
4 speeds, 9, 10, 13 & 15 OD big rig trans, not to mention building Hemi torqueflites
and beefed AOD's and 4R70W's and a stray 350TH here and there.

Was just worried I'd have to have some special tool made out of unobtanium or
something. I can usually make up something that works, but sometimes it gets
to be near impossible.

Looks like from the parts schematic there's several pieces to the synchro/slider
assy - can I get by with just the synchro ring or would it be best to order the
entire assy?

And where's a good place to get that stuff? Wide variety of prices out there!

Don't need the "last forever" good stuff, just good enuf so I can put on maybe
20k miles in the next 2+ years. Then if I keep it, it'll be time for a rebuilt.
I'm 1700 miles away from home working a 2+ year construct job south of Vegas
and had my car stolen a few weeks ago. This is just a backup for bad weather
for my bike and to pull the bike trailer on some of my longer weekend bike trips,
then to haul my stuff home when the job is done. Might keep it, might not after
that. Have other much stouter hauling/towing vehicles at home.

I figure with 75k miles, I can just put everything back together and not worry
about clearancing like if I was putting in new bearings etc etc. Have done that
before, even swapped some parts in my BMW 6 speed cycle trans.

Thanks for particulars on all what I'd need for the 5/6 synchro (and/or slider assy?)
and a good "economical" place to acquire them.

Oh, can I tell if it's got the upgraded 5th synchro without tearing it apart? Will the
tag # tell me? I found

http://www.drivetrain.com/parts_cat...ion_overhaul_kits/ford_m5r1_overhaul_kit.html

but there's even synchro kits on ebay pretty inexpensively, but just the synchros.

Have an oem shop manual, even tho they call that trans a slightly diff model but
have found out it goes by a couple diff names.

Thanks for the info and the encouragement!!

 

[adsm08]

The worst part about this job will be the big nut at the end of the output shaft. Once that is off it's not bad. The speed gears have to be pressed off their shafts, I just checked the shop manual and it says to remove the syncro before removing the gear, so you should be OK there.

I'd get the whole collar assembly myself. It's been a few years since I took one of these apart, but they are pretty simple. I think it was just 3 keepers and 2 retaining rings that hole the collar and syncro to the gear.

92 was the year things changed. You should have the one with the higher tooth count.

 

[trail B2]

If I remember right you don't need in the main box witch helps a lot.The big nut is like 2 1/8 inches need a wrench not a socket for that.Just about 200 ft lbs on that one.If you beat up the little wafers that hold the main nut it's easier to replace that too. If you take 5th gear out it's easy to put in backwards the way the manual shows it and it won't stay in gear.I've had good luck for single parts from Oregon Transmission Exchange call there parts department.

 

[macx]

That's great info - was worried about that big nut.

A wrench I can buy, that much torque is another situation.
My torque wrench I believe just goes to 150, but I've done
enuf torqueing so I should be able to get it pretty close by
going to the 150, then turning to the starting mark if I match
mark it before I loosen it.

That assumes that big nut has to come off?

I was wondering if it could be done without removing the trans,
going into it from the back end. I did a synchro in a small front
driver 4 speed once by just pulling the front tire and the cover
off the outer end of the trans. Being it appears the back part
of the case comes off (now this is without looking at the manual
and diagrams very closely yet) I was wondering if that would
happen to be possible.

Not a show stopper if I can't but it would of course save some work.

All things considered, being I have a very limited time to get this
thing on the road (like this weekend), I think I'll wait for next summer
to do the synchro when I won't likely need it in any big hurry - I ride
my bike to work unless it gets below the upper 30's in the morning and
that's what the forecast low's are starting next week. Trans works fine
except I can't put much torque to it in reverse even holding the
shifter, but I have a spot at work where it will face downhill and I
don't have to back up to get out of the parking spot. At the apartment,
it's a slight downhill backing out of the covered parking spot.

But thanks for the info! Will be sure to save that, and keep that in mind
while doing some more studying in the manual. I do like to be prepared
and be as familiar as I can be with something I haven't done before
when I tackle it.

 

[Will]

I would swap it out for an A4LD. It never has synchro problems.

 

[AllanD]

That's great info - was worried about that big nut.

A wrench I can buy, that much torque is another situation.
My torque wrench I believe just goes to 150, but I've done
enuf torqueing so I should be able to get it pretty close by
going to the 150, then turning to the starting mark if I match
mark it before I loosen it.

That assumes that big nut has to come off?

I was wondering if it could be done without removing the trans,
going into it from the back end. I did a synchro in a small front
driver 4 speed once by just pulling the front tire and the cover
off the outer end of the trans. Being it appears the back part
of the case comes off (now this is without looking at the manual
and diagrams very closely yet) I was wondering if that would
happen to be possible.

Not a show stopper if I can't but it would of course save some work.

All things considered, being I have a very limited time to get this
thing on the road (like this weekend), I think I'll wait for next summer
to do the synchro when I won't likely need it in any big hurry - I ride
my bike to work unless it gets below the upper 30's in the morning and
that's what the forecast low's are starting next week. Trans works fine
except I can't put much torque to it in reverse even holding the
shifter, but I have a spot at work where it will face downhill and I
don't have to back up to get out of the parking spot. At the apartment,
it's a slight downhill backing out of the covered parking spot.

But thanks for the info! Will be sure to save that, and keep that in mind
while doing some more studying in the manual. I do like to be prepared
and be as familiar as I can be with something I haven't done before
when I tackle it.

Jumping out of reverse on a 1993?


That honestly sounds like someone either assembled it wrong

the Rear bearing retainer is smoked...

OR someone messed with the "big torx nut" on the side of the trans.
(Never do this remove the circlip inside the trans and the 10mm retaining bolt on the "flag" and take the big torx shaft out the side as an assembly)

This part is an "eccentric to make the 5th-reverse engagement "adjustable"

And "adjusting it" may resolve your issue without removing the trans from the truck at all



But when you DO take it apart DO NOT slide the 5th/Reverse shifter fork off of it's shaft.

Look on the side of the trans for a 12mm Bolt that retains the shift fork
shaft and slide the shaft and fork out as an assembly (which is how you'll need to put it back in.