Cruise AND mechanical speedometer surge

[rfl]

Been dealing with a bouncing speedometer in a '93 Ranger 4x4, 5 spd, 4.0, since I bought is used about 4 years ago. Every now and then I try something new to see if I can fix the problem, however so far no luck. I got thinking about how the cruise was also surging so figured the next option was to replace the speed sensor but that resulted in no change.

What I have done, in order:
Replaced the gear at the end of the speed sensor (about 10k miles ago)
Replaced the speedometer cable with a new OEM (about 7k miles ago)
Replaced the speedometer with a used head, still broke, just different bounce patters (about 6500 miles ago)
Replaced the speed sensor, verified the gear was in good shape (today)

I gave the truck to may 16 yo, so I would very much like to get the speedometer and cruise working properly. Other than trying another speedometer or having the existing repaired, which I am not sure will help since the cruise also surges, is my next option to replace the gear inside the transmission (looks like a ring)? If so, is this something that can be replace without dropping the trans or trans oil?

 

[adsm08]

If its a 4x4 the speedo drive should be in the transfer case. The internal drive gear is accessed by removing the rear output flange and seal, then it just slides out.

A new seal is about $12, I'd say it is at least worth taking the gear out and looking at it, making sure it has no mashed teeth.

 

[96Indyram]

If your 16 year old has a smartphone they have free Speedometer apps. they can use until it can get fixed. It uses the phone GPS and the one I used for awhile was very accurate! It was always within 1 mph of any speed in any vehicle I was in.
Turn the app on..set the phone on the cluster and drive.

 

[rfl]

If your 16 year old has a smartphone they have free Speedometer apps. they can use until it can get fixed. It uses the phone GPS and the one I used for awhile was very accurate! It was always within 1 mph of any speed in any vehicle I was in.
Turn the app on..set the phone on the cluster and drive.

Yeah, been using an old Garmin since the truck was acquired, but that only works until the truck bounces and the mount drops off the windshield Lots of dirt roads on the way to the trails.

It is 4 wheel, so I will check into removing the rear output like adsm08 suggested. The drive shaft bolts look like they have been on since the beginning of time, so it may turn into a project. Looking at the service manual, the instructions removing the flange seem straight forward. Should I expect any gotcha's in getting to it other than getting the drive shaft bolts off?

Is that about the end of the possibilities (speedometer and the internal gear)?

 

[adsm08]

The only "gotcha" I can think of is the nut being a large size making the socket a tight fit, but I was able to get it off easy enough last time I did one.

There really isn't too much else to be causing it you have been through every other component in the system. Unless the speedo you swapped in was bad, which it may be if the pattern changed.

The biggest issue I know of with the mechanical units is that the gears can strip if the trip meter is reset while you are moving.

 

[Road Angels]

You lubed the new cable? its not kinked some where on install or messed up when you got it, or next to the exhaust, it also need smooth route from transfer to speedo head large round bends, not insulting your abilities but some times thing get hurried and we all make mistakes

 

[bobbywalter]

that should be mechanical.

are you sure you have the right gear? it may just be loose at the head, but likely the gear is ground a bit if the cruise is bad too. sometimes its subtle but it will be convex looking at it.

sometimes its just not seated properly in the t case and you have to pull the retainer and bend it to get it in there all the way.

 

[rfl]

Thanks for all the replies. The speedometer cable was replace with a new, OEM, well lubed unit. It is not kinked, and does turn the speedometer without binding when turned by hand. I did lube the original cable, checked the routing, etc., prior to replacing with a new one so I was very conscious about kinks and lube when installing the new one. The VSS bracket is new, and is not bent. The driven gear that was replaced (first thing that was replaced) was bad, where the currently installed gear is not. As far as being the correct gear, if anything it is the wrong gear for the gear ratio. Its really not possible for it to be one that is wrong for the transfer case.

Taking a closer look at things, it looks like the transfer case was rebuilt or a junk yard item. Not that it matters.

I did pick up the rear oil seal and speedometer drive gear yesterday. Looking around online, the exploded view diagrams I am able to find have me a little concerned that the gear it not replaceable by only removing the oil seal. Has anyone done this?

The transfer case is a BW1350 electronic. The drive gear is the 7 tooth, that is on the metal sleeve.

 

[rfl]

Well I kept looking for an answer and looks like I am going to move ahead and tear out the seal. This article on doing a 2wd to 4wd conversion on a Bronco II shows the gear slides right out.
http://www.broncoiicorral.com/library/2wd_to_4wd_conversion.htm

 

[bobbywalter]

are you sure your gear is cut for the right rotation? theres left and right rotation and i have had problems getting the wrong gear before. but that was running a 23 tooth into a jeep 208 t case.

heres the other rotation...

as opposed to this.

do you have a 16 tooth driven gear? is it red or dark red or grey??


on the older fullsize case and 2wd speedo shaft drives they are 7,8 or 9 tooth where the rbv t case is the narrow gear you pictures which iirc was the same as the 9 on the fullsize case.


i just went back to a 20 or 21 tooth as the 23 never last long in my 208 t cases. i noticed most of the rangers are 16 tooth to 18.


usually the wrong rotation gear bounces for quite ahwile before it quits altogether.


but the vss not seated properly causes bouncing as well. you have a new vss body i assume as well, as the body where the driven hgear and wear causing the loose condition problem internallly. the drive gear on the t case is much tougher then the driven gears on the vss and rarely get boogered. but it is possible for sure.

 

[rfl]

yes, I am sure it is the correct gear. I just got through taking it for a test drive after replacing the drive gear - steady as a rock! Old one was extremely dished out.

thanks again asdm08 for the direction.

 

[bobbywalter]

the dish is what i was referring to by convex.....which i should have said concave.




apparently the previous owner of the case did have the wrong driven gear.


the funny thing about that though, the wrong gear may have worked better on the old drive gear

 

[rfl]

the dish is what i was referring to by convex.....which i should have said concave.




apparently the previous owner of the case did have the wrong driven gear.


the funny thing about that though, the wrong gear may have worked better on the old drive gear

not sure if anything would have grabbed on to it, but yeah, jamming the wrong one on to it may have at least got it to make consistent contact. As you can see, it was shot:

FWIW, it was not that dirt. Fished it out of the trash bucket to get a photo.

 

[adsm08]

Hmm, I think you found a problem there Mister.