I was going through old posts about speedometer issues. This morning my speedometer didn't give any reading when I first started driving. After a few miles it started working, then it quit again, and then worked intermittently for a while, and then started giving a low and wavering speed reading. Eventually it started working correctly again after 20 miles or so. The odometer quits with the speedometer, so I'm thinking it might not be the gauge itself that's bad. I checked the ground wires on the back of the speedometer and the other wire connectors back there but everything was tight. This summer I'm at Grand Canyon and I've only been driving the coach every couple of weeks to the grocery store in Flagstaff and back, which is about 150 miles round trip. This is the first time I've ever had a speedometer issue. While going through old posts I noticed people mentioned a grease zert is on the speedometer sending unit. Is that supposed to get greased with the rest of the chassis? I suppose I can call an Allison transmission dealer to ask that question. I also noticed a lot of people had to replace or rebuild their speedometer gauge, but not many had to replace their sending unit. I was pleased that my cruise control continued to work without the speedometer. I know from experience that 1500 rpm is 60 miles per hour with my coach in high gear so the speedometer isn't a vital gauge ...at least not like the temperature gauge, which definitely is vital. My plan is to check the sending unit to see if I can find anything wrong with it. If no problems are found I'll probably leave it alone until the speedometer quits. I think it'll be a lot easier to troubleshoot after it stops working. I could waste a lot of effort on it now and never know if I really fixed it because it's still working. Most of the posts I read were several years old. Do any of you folks have new information about finding these speedometer problems?
Scott I have experienced the same thing on our coach,however ours would only do that when the temps were in the 30's and 40's and after setting for awhile. Last time we were leaving camp Verde last fall. Like you I have checked things out and found nothing. I did clean the tranny and engine and haven't had the problem in awhile. ^.^d
Scott I just went through all that with mine.
On mine there is a electronic pickup. It's on top of the rear Trans tailshaft housing. I replaced that and it didnt fix the problem. I replaced the gage everything works fine now.
Where did you purchase the replacement? Our works fine (probably just jinxed it), but always nice to have a "dealer" in mind for the future.
When replacing gauges on two previous coaches, I switched over to: ISSPRO.com - Quality Gauges, Tachometers, Speedometers and more! (http://www.isspro.com) Google them for outlets. ^.^d
The original Stewart Warner gauges can no longer be found, but if you find anyone who has done the "Glass Cockpit' conversion They may have an old one??
My Tach' was the first thing that went and then the speedometer started playing up so I did the conversion. Sorry, my gauges have long since departed.
Speedbird 1
Mine went out a couple or 3 years ago. I wanted to rebuild but the shop I took it to said no way. No parts. :( Looked for another analog milage unit and no go there either. Settled for a new digital milage unit off ebay. It came with instructions for the new wiring. It was an easy change out.
VDO SPEEDOMETER 85MPH GAUGE #437-152
Just checked ebay and prices have gone up! I paid $53 for mine all the ones I see listed are $160!
vdo 437-152 | eBay (http://www.ebay.com/sch/i.html?_from=R40&_trksid=p2050601.m570.l1313.TR0.TRC0.H0.Xvdo+437-152.TRS0&_nkw=vdo+437-152&_sacat=0)
see ya
ken
This is the one I bought
http://www.egauges.com/ProductDetails.asp?ProductCode=437-152&gclid=Cj0KEQjwuJu9BRDP_-HN9eXs1_UBEiQAlfW39iY5urMMQa1KoaRTtQdIkj5hsMMaD5zju71rT1p24VgaAh8I8P8HAQ
...so basically it seems about the same as before, quite a few people have replaced the gauge but very few have replaced the sending unit ...what about the grease zert, should it be greased with the rest of the chassis? ...not that I've actually crawled under there to see if the zert is really there, but just basing the question on old posts I read on this forum
It's really there. The problem could also be the speed sender, the gear that drives the speed sender, or the gizmo attached to the gear that drives the speed sensor.
That was a poor choice, Ken. If you had chosen, instead, the 160MPH GAUGE, your coach would go MUCH faster. 8) Plus, it's cheaper!
New VDO Genuine Speedometer 3 3 8" 86mm Cockpit 437 053 160 MPH | eBay (http://www.ebay.com/itm/New-VDO-Genuine-Speedometer-3-3-8-86mm-Cockpit-437-053-160-MPH-/261331449211?hash=item3cd891757b:g:Sj4AAOxyRNJSh5ua&vxp=mtr)
Not all coaches have the gear driven sender that needs greased seems like the electronic controlled Allison transmission does not have the gear that needs greased
Ok, I have been reading this posting like others before and have not come to find out if these gauges are replaced because of one issue over the other. Said another way, is the biggest problem the odometer (how fast you are moving) versus the digital recording of how many miles traveled ( milometer)?
My problem is the latter, so does this mean it is just the Digital part of gauge that is bad?? The speed of travel is like others- analog works fine.
JohnH
Scott crawl under your coach look at the rear tailshaft housing on the transmission. The sensor if it's like my 91 is on top of that housing.it will have wires coming out and there will be a connection plug on the left side of the transmission.There is 1 bolt that secures it in place it has a oring on it and it presses into a hole on the housing. If you decide to try and replace it be forwarned, it has been there 25 year's mine broke, I had to use s angle attachment on my drill and mirrors to drill a hole in it so I could then put a screw into so that vice grips on it and use pry bars to get it out.It wasn't easy and it was a pita! With the new sensor I still had the same issue. New speedo solved the problem. Were I to do it again I'd replace the speedo first. The sensor is a magnetic one and there isn't much that should go wrong on them.
It's your time your money that was just my firsthand experience dealing with my speedo on my 91.
On mine which is like yours, the lcd screen went bad in the odometer. Non repairable at the cost of a new one with the correct mileage put on it by the seller.
My 91 GV has only an analog speedo and it is driven by the mini-gen on the transmission. I replaced the mini-gen and all is well now. Disconnect the two wires on the mini-gen and read thru it with an ohmmeter. It should show continuity, but I don't remember what the resistance is. If it is open circuited, replace it. My mini-gen came out easily , you just have to pull the tang from the old one and install it in the new one. Have a great day ---- Fritz
Any idea where to buy this drive adapter?
You mean what's in the picture? You can have it.
Twig, that adapter is necessary if you want both Speedo and Cruise control, both senders are needed. Ours fell apart and Steve just put the speedo in the hole so atleast we have that.
If anyone knows where to buy the device that's shown in Twig's picture please let me know.
message me your address.
Stump, I read your post along with several others. I'm just gonna look at the sending unit to see if I can find anything wrong. I don't intend to remove or disassemble it because it's currently working. When it stops working I'll start removing and disassembling things after I troubleshoot. I was just trying to educate myself ahead of time by reading old posts on here. In my experience it's usually difficult to troubleshoot something that's still working... and I really hate breaking stuff that still works
Scott, Here's a troubleshooting flow chart to help you out:
Scott here is my thread on the sensor
Speedometer sensor removal (http://www.foreforums.com/index.php?topic=26733.msg215962#msg215962)
Here is what mine looked like.
Look at this on eBay 23013334 s Magnetic Speed Sensor Assembly for Allison Transmissions | eBay (http://www.ebay.com/itm/281353532755)
@Scott,
I can't say for sure but I'd bet money that your speedometer is your problem. Mine worked intermittently for about a year before it died completely. The original analog (milage) speedometers seem to have a limited life. Replacement is in your future. The good news is that while it's still working you have time to find one on ebay at a reasonable price. The bad news is my tachometer just died a week or so ago. So you have that to look forward to.
see ya
ken
[ The bad news is my tachometer just died a week or so ago. So you have that to look forward to.]
Ay Yi Yi!
Don't mean to steal this thread but I have speedometer problems also. I have attached a photo (I hope) of the part I think is bad. This mounts on the transmission and it might be called the mini generator. Anyways the sort drive cable's end that looks like an old speedometer cable slides into this piece but it just seems to turn freely as if the female socket is worn out.
Anyways what is the proper name for this part and where can I find one?
[/quote]
You're not stealing the thread. You're exactly on topic with speedometer issues.
Jerry,
Identifying and locating obscure parts for old motorhomes can be a challenge. It is helpful to provide as much info as possible when asking for help. In this case, you might specify what transmission you have - I'm guessing it is a Allison MT643 - and what engine. I would also like to see a more "zoomed out" photo, so I can see what the other end of the electric wire looks like, and what the drive cable looks like (both ends). Photo of the attachment point on the transmission would be nice.
I think your best bet might be a really good (local to you) "speedometer shop", if such things still exist. Back in the day, these shops used to specialize in making/supplying adapters to mate
any transmission to
any speedometer.
You could try a Allison transmission shop, but they will probably say it is not a Allison part, so can't help you.
Without a part number of some kind, a online search will be difficult. You will find lots of parts that look similar to yours, yet might not work at all. Besides having to mechanically screw together correctly, the part also has to be electrically compatible. The mini-gen "generates" a electrical signal that must be translated by the speedometer into MPH. The frequency or voltage or whatever of the mini-gen and the speedometer must match.
Wish I could be more help. The thread linked below shows the "process" a Barth owner went through to find this kind of part. In the long run, it might be easier to just install a new aftermarket speedometer. Do you have cruise control? Does it still work?
Hall Effect Sensor - VSS Sensor - Speedometer Ratio Adapter - Topic (http://www.barthmobile.com/eve/forums/a/tpc/f/3631087061/m/1643977177/p/1)
Chuck & Jeannie, Thanks for your response. I will try to get the photos later today. For now, to answer some of questions, the cruise still works, the transmission is a 4 speed Allison ( I'll try to get the numbers when I take the photos) the engine is a Cat 3208. I have sent the speedometer head and what I thought was the generator to, I think, Texas Speedometer and they said they checked out fine. I have put off troubleshooting the problem for over a year and have been using my GPS as a speedometer. Of, I had no oedometer.
On your suggestion of a new speedometer, will it come with the generator and adapters to connect it to my transmission and cruise?
Thanks again.
I don't know - my speedometer still works, so I have not researched that subject.
The engine and transmission info will be helpful to anyone trying to answer your questions. You should add these to your signature.
You might try using the Forum "Search" function - it will often provide the exact answer you seek. Try searching for "new speedometer", or perhaps "replacement speedometer". See what other members have done in this situation. For instance:
'93 U300 speedometer (http://www.foreforums.com/index.php?topic=17192.msg113678#msg113678)
The Speedometer/Cruise Control "T" fitting turns out to be a Bendix Product. Am going to visit a Allison Dealer soon to find out if they have a cross over to it, since Bendix is long gone.
Jerryetc ---- I had very good service from Steve @ Portland Speedo Service for solving my speedo problem. After doing the troubleshooting that he recommended, I ended up replacing the mini-gen sender on my Allison 4 speed. The new mini-gen sender is an "isspro P/N R 8970, date code 2415". Give Steve a call @ 1-800-634-2145. I'm sure that he can help you thru this. Have a great day ---- Fritz
Fritz, Did your mini-generator look similar to mine?
Thanks to all for your help. I took Fritz"s advice and called Steve at Speedometer Service in Portland. It appears that my drive pin may be the problem, but I am mailing both the mini-generator and the drive pin to Steve and he going to check it, fix it or replace it. Also Chuck I am going to take your advice and expand my coach information on my page.
Jerry,
Glad you found some help on your speedo problem.
I see you have added the coach data to your signature. Excellent! You might double-check your transmission model number. Most of the Allison 4-speed model numbers start with a "6", and most 6-speed model numbers start with a "3" or a "4", which is really kinda bass-ackwards when you think about it.
Thank you Chuck. I changed to 643. I don't know where that 463 came from.