Engine/Transmission (1994 - 1998) Should I bite the bullet and get a NV5600?

[GAmes]

I think my 5-speed has died, again. This is my third or fourth transmission, lost count. There is 104k on this one, mostly highway, 70% towing. I've read that a conversion is about $4k, so I'd have to replace at least 3 more 4500s to make that up, plus how much longer would a 5600 last? Lastly, and this is the deal breaker, has anyone figured out how to get the speedometer to work on a 97? Thinking out loud here and trying to justify the upgrade, cuz I'd really like to have a gear between the 3rd and 4th I have now.

 

[Matthug]

Whats going wrong with your 4500's? Where are you getting them from?

 

[Mundgyver]

For a speeometer, just use a Garmin GPS.

 

[Vaughn MacKenzie]

There's been more than one guy put a NV5600 in their 12-valve. I never heard of the speedo being an issue. They probably use the sensor that comes with the NV5600 and they should be able to patch into the '97's original speedo sensor wiring.



The NV5600s aren't the cure-all-fix-all, I know LivinEZ on NW Bombers burned one up on his '04. 5 at about 150,000. He tows heavy. Actually come to think of it he's on transmission #3. There is a weakness in the engineering of the oiling to one area of it which doesn't let it carry off enough heat or get enough lube and will ultimately lead to failure. I'll see if I can find the thread.



Ironically his last truck was a '97 with the 5-speed, and a GearVendors unit in it. I believe except for a couple 5th gear fixes he had the original transmission when he sold it at 610,000. He towed heavy with it.



Vaughn

 

[Mundgyver]

See if Cummins builds an adapter ring for one of these. Then you can pull anything you want.



http://www.roadranger.com/NASApp/cs...nd+Solutions&c=Page&cid=1132491775960&inner=y

 

[GAmes]

What's wrong with 4500s? Nothing if you only drive 10 to 15k a year. I drive that every month. This one is losing it's synchros, the last ones had bearing failures. The speedo is an issue because the sensor on a 97 is gear driven from the transmission, the later models with the 6 speed take the reading from the differential sensor. GPS won't work for the odometer, something DOT is interested in from time to time. Oh, and the Eaton's 6th gear isn't overdrive, it's 1:1. Worthless to me, besides the fact they only say it's better than an automatic... duh

 

[Matthug]

I wasn't asking whats wrong with 4500's in general, I was asking what keeps going wrong with yours.

Have you been getting rebuilds from the same place everytime? Guys run 4500's in 500-600 HP daily drivers all the time, you have to build them right so they can handle the power.

Also if you drive it like a car and speed shift everywhere you go that will put your synchro's out pretty quickly.

 

[GAmes]

I'm getting my rebuilds from Standard Transmission, I don't abuse them and I only dynoed about 300hp/600 tq to the wheels. I do however apply that torque real often pulling trailers up hills. They just wear out between 100 and 150k. I'd like to hear how much longer a 5600 might last, plus I'd like that extra gear.

 

[walexa07]

One thing that some assume incorrectly is that the 6-speed transmission has an extra gear above the nv4500, but actually 5th is direct in the 6-speed just like 4th is direct in the 5-speed, and both overdrive gears are almost the same reduction ratio. Other than that, I don't believe you can still buy a brand new nv5600, only rebuilds, if that matters. Dan at quad 4x4 would be a great source to give a call and get his opinion about the nv5600 versus the nv4500's. Some also incorrectly assume that the nv4500 doesn't require fluid changes and this shortens the life of them as well. I'd say that a correctly rebuilt nv4500, with regular fluid changes per quad 4x4's recommendations should give you long life. Even 100 to 150K miles between rebuilds towing heavy doesn't seem too bad to me. If you were only getting 30K to 50K between rebuilds I could really see your frustation. Anyway, good luck.



Waylan

 

[GAmes]

Thanks,

The extra gear I'm talking about is the one between the 3rd and 4th in the 4500. Sometimes 3rd is too low and 4th is too high. I also change oil every 50k and except for this time have used nothing but syntorq. This oil was put in by Blumenthals after a clutch replacement and it is one they recommend. There is 47k on it and I had planned on changing it this weekend, that is until the growling started. You are right, 100k and more isn't bad for constant towing, I'm just exploring alternatives. Blumenthals do the conversions and that is closer to me than quad 4X4. Standard Transmission is even closer but they don't have their own shop for R & R.



I'd still like to know about a speedometer fix.

 

[Vaughn MacKenzie]

The speedo is an issue because the sensor on a 97 is gear driven from the transmission . . .

Correct, but there is a sensor on the transmission that reads the gear and sends a signal to the PCM, which drives the electric speedometer in your truck. So what you do is use the speed sensor that comes with the NV5600, cut the wiring to your current speed sensor off at the sensor, then patch the wiring of your truck to the NV5600's sensor wiring. Make sense? I am assuming this works, I would contact a vendor who does NV5600 transmission conversions.



I think it was 1989 or 1990 that Dodge switched from mechanical cable drive speedometers to electric head units driven by the PCM.



Vaughn

 

[walexa07]

One other thing to consider on the nv4500 is to overfill it. I am able to get 6 quarts in mine through the top cover. The transmission has a vent tube so I would assume if it's too overfull it would come out there. Been running mine like that for 50K and no problems. I would at least overfill it by 1 quart. You can also add the filter kit... ... I think genos and I know quad 4x4 sell them.



Waylan

 

[Vaughn MacKenzie]

GAmes, do you run a temp sensor in your transmission? I do in mine and once when towing "not too heavy" the oil temp reached 220 degrees. Maybe your transmission is getting too hot. If I was hotshotting I would have a temp gauge and fastcoolers for sure.



Vaughn

 

[HRDROKN]

Trans temp

What would be considered "too hot" and what is the normal temp??? Does the cooler really make a difference? I think I will hook up my transmission gauge when I do my swap to the NV4500.

 

[GAmes]

I do have a temp gauge and fast coolers, so I already put 6 qts in at oil changes. I have heard that the 5600 needs an extra qt, but not the 4500. I have only been over 200 degrees once, pulling a very heavy 5er up cabbage hill in Oregon on a very hot day. I didn't have a gauge before the coolers were installed, so I'm not sure how well they work, but I figure the extra 2 qts of oil are a bonus. Today, in TX, pulling an 11k 5er, air temp about 70 the gauge went up to 160 or so. I have found that even when the transmission is destroying itself the temp doesn't rise over normal. Maybe it would if only the bearings were going bad.



Oh, with the coolers you can't use the filter :{

 

[jrobinson2]

Correct, but there is a sensor on the transmission that reads the gear and sends a signal to the PCM, which drives the electric speedometer in your truck. So what you do is use the speed sensor that comes with the NV5600, cut the wiring to your current speed sensor off at the sensor, then patch the wiring of your truck to the NV5600's sensor wiring. Make sense? I am assuming this works, I would contact a vendor who does NV5600 transmission conversions.



I think it was 1989 or 1990 that Dodge switched from mechanical cable drive speedometers to electric head units driven by the PCM.



Vaughn

I didnt think the NV5600s ever came in a truck that used a trans speed sensor?? All the 98 and newer trucks I've looked at had the speed sensor in the rear differential and no provisions for a sensor on the trans.

The pre '98 4x4s are no problem because the t-case has the sensor, the 2wd's are a problem...

 

[Vaughn MacKenzie]

I think you're right Jrobinson. I don't know what the 4x2 guys would do, but the pulse rate may be quite a bit different than reading the signal from the trans or transfer case.

 

[Turbo Thom]

GAmes... ... ... ... . don't feel to bad. I'm on my 5th transmission myself, and this one is howling like a wolf on the prowl. I use the US gear overdrive, and still can't get the tranmissions to stay with me. ST here too. I too have considered the 6 speed and don't know if I would be any better off. Ive' had 2 burn up in 8,000 miles. Replaced free but still I paid for install, on the road also.



. . Preston. .

 

[GAmes]

Thanks for all the responses. I think I may only have one synchronizer failing, so hopefully it won't be an expensive rebuild. ST has been great and stand behind their product. They once sent a trans to me in Salem, Or and paid for the R & R as well. At least this time I am close to them.

 

[JBeasley]

I've done a 5-speed to a 6 speed in two 97 3500's. Good luck finding one. The speed-o was not an issue in either one cause it was in the rear end. The only thing I had to do as far as wire splicing was for the back-up lights. I had to buy a pig tail to fit the 6 speed and splice it in place of the 5 speed plug. It's been a couple of years since I've done one and I'm getting ready to do another, but I can't find a trans. anywhere. I don't have a core and all the places I've contacted to get a reman. will not sell me one unless I have a core. I have another thread posted on here asking about Pheonix Reman. Transmissions. They have the best price and a good warranty and they will actually sell me one without a core $1000 extra OUCH! Any info on them good or bad would be great. AS far as if it's worth it; absolutely. I ran hotshots and after 3 5 speeds I made the switch. I liked it so much that when the 5 speed went out on my personal truck I 6 speeded it too. If you pull alot it is well worth it. The gears are split much better so you don't have to work the engine so hard to get up a hill. I feel your pain between 3rd. and 4th. on the 5 speed. In 3rd. your over revving the engine but if you shift to 4th. then your lugging it and your egt's head for the red. Definetly overfill the 6 speed a quart. My 6 speeds have lasted alot longer than my 5 speeds ever did. I also noticed an increase in mpg. Call me crazy but both my trucks also seamed like they had more power because the rpm's won't drop below peak torque between shifts now. Sorry to post such a long thread, just trying to help. Good luck