Lost reverse?

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Rob

Rob

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I just lost reverse in my 90 RAM, never had a problem with it before. Put it in reverse this morning and nothing, drive is fine. Any ideas on this, it's a 727. I'm hoping it's a cheap fix, not wanting to get it rebuilt :banghead:
 
drop the pan...look at the rear servo and rear band....either the servo is cocked in the bore...or the band broke...
 
I agree with 69MOPE, the rear servo can actually split, therefore trans fluid leaks through, no pressure to to engage rear band = no reverse
with the sump,filter removed, if you can remove the pin that the rear lever pivots on, (sometimes there is a tab on the case you may need to grind off)
Then compress the servo with a G clamp, remove the circlip, the piston will now drop out when you loosen the G clamp.
It is potentially possible to repair this without removing the box.
 
The rear servo issue can definitely cause no reverse but since this occurred have you driven it to verify it still has 3rd gear? The front clutch pack has to work for 3rd and reverse to work. If it also lost 3rd it's that pack burned up or the piston seal in it blew. Before you drop the pan drive it to make sure it has high gear.
 
Watts0001 said:
if you can remove the pin that the rear lever pivots on, (sometimes there is a tab on the case you may need to grind off)
Click to expand...

Uhh, dude! If you grind off the bump that holds the pin in whatcha gonna do to retain the pin when you put it back together??

You don't need to, or ever want to grind that bump off. That bump that holds the pin in is on the extension housing. Worse comes to worse you take the extension housing off. But really there's no need to remove the pin at all. If fact I guarantee if you do you'll have one heck of a time getting it back together with the trans. in the car, if you can even get it back together at all. All you have to do is unscrew the band adjuster screw all the way out of the servo apply arm and using a long thin flat blade screwdriver push up against the band and the connecting strut will fall out allowing the servo apply arm to drop down out of your way. When you fix the servo you push up against the band again with the long screwdriver and slip the strut back in place.
 
fishy68 said:
The rear servo issue can definitely cause no reverse but since this occurred have you driven it to verify it still has 3rd gear? The front clutch pack has to work for 3rd and reverse to work. If it also lost 3rd it's that pack burned up or the piston seal in it blew. Before you drop the pan drive it to make sure it has high gear.
Click to expand...

No I haven't driven it. It's at the end of the driveway and at over 3 tons I'm going to have to drag it out of there and take it to a trans shop. My skills are in the body and paint dept, I can wrench on motors to a reasonable extend but transmissions are over my head.
 
...so if it is a band I gather it has to be yanked and torn apart?
 
it is not very hard to take the pan off and try to see if the band or servo has a problem...
 
70aarcuda said:
it is not very hard to take the pan off and try to see if the band or servo has a problem...
Click to expand...

I could rmove the pan but

I have no idea what a servo looks like? no mention of it in the factory shop manual either.

..and if it is the band the trans has to come out and be rebuilt basically?
 
[ame="http://www.youtube.com/watch?v=rXtcTIGfdY4"]Part 14. Front & Rear Servo Arm Assembly - YouTube[/ame]

two second to google.
 
[ame="http://www.youtube.com/watch?v=Aci45eVwGJY"]Part 17. Front & Rear Band Strut Assembly with Rear Band Adjustment - YouTube[/ame]
 
Thanks Tony, those were very informaitve clips. Sorry if I offended you, I honestly was trying to dummy down my questions to keep it as simple as possible. What broke and does the bloody trans have to come out depending on the possible problems? Given the clips had the trans out and gutted for the servo, and out and assembled for the belt "adjustment" I must conclude I'm screwed, such is life :(
 
If you find it is in the servo you can buy a billet steel one off of eBay called a super servo. It is made for the 727/518 trans. I just put one in my 46re I will admit it being made of steel made me nervous but after breaking two stock servos I had had enough of that. I have only drove it about 300 miles but so for so good.
 
http://www.bulkpart.com/2/product/A727servo/S22912.html

these work just find also

no offense taken..just if you were going to take it to the trans shop...it is better to know what you need fixed...otherwise they will get a
jar of Vaseline out on you..

and if you are interested I have a very good DVD that shows how to rebuild a 727....watch the video and see how simple they are..

if you want a copy ...pm me your mailing address..
 
I take it by your responses that it's more of a case of you don't have any desire to work on it since your a body man, not a mechanic. As a body man I'm sure you know changing a door and aligning it is something a lot of people haven't done yet it's really a pretty simple job. Dropping the pan and following the extremely simple instructions we gave on how to check things is just as easy as changing and aligning a door. If you have the ability to swap a door and align it IMO you have the ability to check the servo. Please don't take this as a derogatory post dissin you as that's not what I mean. You said in your last sentence "I'm screwed, such as life". A person doesn't have to lie down and let themselves be screwed. I can understand the issue of it being in an inaccessible place and needing pulled out but don't you have a buddy with a truck that could easily do that? I'd think anyone that does body work has towed a vehicle.

BTW: as we said earlier the trans. does not need to be gutted to replace a servo or adjust a band.
 
Rob said:
Thanks Tony, those were very informaitve clips. Sorry if I offended you, I honestly was trying to dummy down my questions to keep it as simple as possible. What broke and does the bloody trans have to come out depending on the possible problems? Given the clips had the trans out and gutted for the servo, and out and assembled for the belt "adjustment" I must conclude I'm screwed, such is life :(
Click to expand...

The servo can be fixed in the vehicle, but if the band broke it has to come out and be torn all the way down.
 
70aarcuda said:
http://www.bulkpart.com/2/product/A727servo/S22912.html

these work just find also

no offense taken..just if you were going to take it to the trans shop...it is better to know what you need fixed...otherwise they will get a
jar of Vaseline out on you..

and if you are interested I have a very good DVD that shows how to rebuild a 727....watch the video and see how simple they are..

if you want a copy ...pm me your mailing address..
Click to expand...

I would be interested in watching that but I'm not likely to take on the build at this time. Know your limit play within it.

fishy68 said:
I take it by your responses that it's more of a case of you don't have any desire to work on it since your a body man, not a mechanic. As a body man I'm sure you know changing a door and aligning it is something a lot of people haven't done yet it's really a pretty simple job. Dropping the pan and following the extremely simple instructions we gave on how to check things is just as easy as changing and aligning a door. If you have the ability to swap a door and align it IMO you have the ability to check the servo. Please don't take this as a derogatory post dissin you as that's not what I mean. You said in your last sentence "I'm screwed, such as life". A person doesn't have to lie down and let themselves be screwed. I can understand the issue of it being in an inaccessible place and needing pulled out but don't you have a buddy with a truck that could easily do that? I'd think anyone that does body work has towed a vehicle.

BTW: as we said earlier the trans. does not need to be gutted to replace a servo or adjust a band.
Click to expand...

I can drop the pan and have a look but if you don't know what you're looking for it's of limited help. I've had 2 back surgeries in the last 3 years so yanking out a trans and transfer case isn't appealing. The I'm srewed was referring to this not being a cheap fix, I was hoping that it could be fixed with trans in.

TrailBeast said:
The servo can be fixed in the vehicle, but if the band broke it has to come out and be torn all the way down.
Click to expand...

Thanks, that was really what I wanted to know. I really think it was the band breaking when I shifted it into reverse, felt real loose or easy?
 
Rob said:
I can drop the pan and have a look but if you don't know what you're looking for it's of limited help. I've had 2 back surgeries in the last 3 years so yanking out a trans and transfer case isn't appealing. The I'm srewed was referring to this not being a cheap fix, I was hoping that it could be fixed with trans in.
Click to expand...

Didn't the video's show the servo and band and what to look for? I didn't watch them so I'm not positive but I thought they showed how to inspect them. I can post some pics if you like. I've had 2 back surgeries in the past 20 months so I can totally understand your apprehension to yanking a trans. but as we've said quite a few times in the thread a lot of the time it's the servo that breaks, in fact the vast majority of the time it's the servo that breaks and it is repairable with the trans in place. And it's a cheap fix.

The problem with just taking it to a shop is so many times we hear of how the customer got screwed. Lets face it, if you drop it off and they take it apart without you actually seeing it they could hand you a pile of parts from most any transmission that was trashed and say their from yours and you need to cough up $2000 for a complete rebuild when it might really only be a $75-100 repair. And after you give em $2k get it back something still doesn't work right (because they either didn't really rebuild it or did a shoddy job) and they give you the run around. Seen it happen numerous times. I swear I hear more horror stories about transmission shops then any other type of repair shop. That's why if you have any mechanical ability at all it's always best to at least drop the pan and have a look. Then if it looks trashed and your in a situation where you can't rebuild it take it to a shop. At least you'll know it really did need rebuilt. See what I'm saying? Just trying to help.
 
I broke a band in my transmission a bunch of years ago and lost reverse, so I'd start with that.
By the way, I thought an automatic rebuild was over my head as well. You're a body man and can rebuild an engine. I recommend you rebuild it and you'll learn a new skill and save a bunch of money. Buy the book by Karl Munroe (pretty sure...I know it's Munroe...amazon.com has it for about $20...read the book, then shop TCR, A&A...shop around and get a good rebuild kit, then if you want better performance / longevity, buy a Transgo shift kit (TC-2? something like that) and install using upgraded clutches and steels. Depending on whether you're towing with it or not, I'm sure a stock rebuild will do fine. You can rebuild it with upgrades for around $300. I rebuilt my first one using this book, upgraded parts (Alto clutches and Kolene steels), using the specs in this book (which included using a snapring from a GM application to set clutch clearances) and hung it behind my 493 RB stroker that puts 528hp to the rear wheels. I've been racing it and street driving it for three years and it shifts great and has no issues at all. You will be glad you did. You might have to get creative to compress the little coil springs to get a snap ring out, and you'll probably have to buy a pair of funky needle-nosed, internal snap ring pliers, but then you'll have them for later. Good luck, let me know if you man-up and pull it off! :burnout:
 
It's Carl Munroe's book...on eBay also for $22...parts kits on there too, but depending on how specific you want to get at building it to hp specs, you may not need anything more than a stock rebuild kit, which you can find for between $100-150. Good luck, you can do it and save a lot.
 
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