I bought a new gauge cluster and it came in the mail today. It is the 145 mph one, and suddenly I don't trust mylsef installing it. Also, I supposedly need a new oil pressure and water temperature sending units and I dont know how much they are or what they look like. If anyone can help me out, or tell me about how they did theirs easily or something thatd be great. I also wanted to swap the odometers, so any stories about doing that successfully would be helpful too. Thanks a lot guys.

 

Just take a deep breath and put it in. I've never done it myself, but it can't be that hard. Or could it...

And is switching odometers legal?

 

Well I want the 145 speedo, but i want the mileage to read correctly for the car. i need to get the new sending units first anyways...if this is true that i need them.

 

mileage is exempt on the title because the car is over 10 years old. (at least in NY)

As far as installing the cluster, its straight forward. a few torx on the trim bezel, and a few nuts holding the cluster to the dash.

 

Yea, but I kinda wanted the odometer to read right for myself...not really for legal reasons. I guess I could just write down the mileage and do the math. and did you do it? and if you did, did you need to change those sending units?

 

As for the installing part, just take your time and dont force anything

As for getting the mileage the manufactures website may have an FAQ for that or just email them. If all else fails write the original mileage on the back of the new speedo.

As for sending units they are very small simple units, threaded nipple on one end and wire connection on the other. Should be under $20 ea.

Edit: heres a generic autometer sending unit pic so you know what to look for.

 

fwiw, I didn't have to change any senders. I went from a '90 dash stock with the 120 speedo to an '87 140 speedo. I think the discrepency lies in wether the dash has an oil pressure gauge or dummy light, same for the water temp.

 

^^^ exactly, but your best bet is to just change them to guarantee 100% functionality. They are fairly cheap and are probably going to crap out soon anyways

 

I haven't tried it on a firebird speedo, but on a camaro speedo, it's a piece of cake to open it up and swap the odometer with your original one so that you can maintain your milage. If you tinker with the spare one a little bit, you'll also figure out how to roll it, which comes in useful not only for dirtbags who try to defraud buyers, but for those of us who want new gauges to display an accurate milage.

 

There may be some info in the following link that will be helpful:

https://www.thirdgen.org/techbb2/sho...hreadid=249244

JamesC

 

Well heres the good news. The speedo works. Heres the bad news. The temp stays spiked way above the highest temp on it, the oil pressure gauge also stays spiked, the voltage one reads 2-3 higher than my old one did, and the gas gauges is all screwy and bouncy, and the trip odometer is broken, and the tach reads 500 rpm too high at idle, and i think even more difference at around 2500rpm (havent gone farther yet). So basically i got this whole cluster mainly for the speedo, but its the only thing that works right (beside the regular odometer. ugh!

 

Back when I was selling clusters regularly, I always recommended swapping the speedo head into the buyer's cluster. In that way, the buyer was assured that all would function correctly (providing all function correctly before the swap).

JamesC

 

I mean the gauges dont really matter that much to me. I could care less if my tach says 2500 when im actually at like 2000. and the gas gauge doesn't really matter that much to me, i think its straightening out. How could not reading the other ones be a problem. I mean I have taken long trips with absolutely no temperature or oil pressure problems. and i could live with no trip odometer. it just kind of gets me mad that the guy said everything worked. anyway, ill get back on what the seller tells me to do about this little problem. I might just wind up putting the speedo in my old cluster even though it didn't really work perfectly, but definantly much better.

 

you can live without a gas guage and trip meter??

how ya gonna know how many miles uve driven? gonna estimate stuff?

Its just plain helpful to have oil pressure / water temp also handy...

coolant leak on the highway u dont know about...could be too late

lots of stuff...think about that one for a minute.

Id spend the extra time and figure out how to hook everything up correctly cause chances are you are gonna actually want all those things youve mentioned...

 

thats what you get for swapping out clusters for a stupid 145mph speedo
(of which, maybe if your lucky, you might hit someday)

sorry i find the swap annoying as 10k tach's in our cars

 

i think i might just use the old cluster, and change the speedo to the new one, and then just sell the new cluster with the old 85.

also, i have hit 85 before and i dont want to break anything. I had to get over a couple lanes to maintain my speed and not get b*tched at by everyone. If I had a 115 I wouldnt care either, plus the 145 looks cool too.

 

Winna Winna chicken Dinna!!

I second that. Pull it back apart, and just replace the speedo. Everything will work fine then.

JamesC, nice write-up on the speedo fix. FWIW, I did the same fix on my 145 speedo, but used thick dental floss instead of wire. Has worked fine for over 10 years now.

 

yea, ill take it back out some time this weekend and switch the speedos, thanks for the help guys.

 

It's conceivable, I suppose, that the cluster isn't properly seated, and as a consequence contacts aren't mated up correctly. Did you tighten down the 10mm speed nuts? By the way, did you need the senders before the swap? If not, you don't need them now. The swap is just that, one cluster for another (providing idiot lights aren't involved).

JamesC

 

if the gauge ground isn't clean and making good contact, the instruments will behave very strangly.

 

thats insteresting. but i think i will just use the old gauges, the "glass" is much cleaner and i know the gauges work. and if i did any of the things you mentioned, I would have to remove and put back the gauges anyways, so might as well. thanks.

 

THe temp and oil pressure gauges stay spiked bc of the old sending units, see those controlled a dummy light, and ground out the connection full time so the light stays off, but since there is now a guage in place of a light, the needle will go as far as it can, just replace the oil and temp sending units with the CORRECT replacement (ie specifi the cars engine when you go the Gm dealer) And as for the tach, are you sure the cluster came out of a camaro with the same engine as you? if not this could cause problems like that.

 

thanks for the advice, but i went ahead and swapped the speedo head into my old cluster, and now every gauge works. Now i just gotta get an explanation from the guy who sold me the gauges.