Engine/Transmission (1994 - 1998) Another 5th gear gone South

[TurboSandman]

I'm only at 120K on my '97 2500 with mild mods and my 5th gear abruptly stopped transferring power during highway cruise; no noise, vibration or harshness and 1st through 4th work fine. My diagnosis is 5th gear nut unscrewing due to my power mods and I have continued to drive it locally. Anyone disagree with my assessment?



I've searched the boards and find the fully splined mainshaft is not a universal cure-all but cannot find anyone with experience with the Quad 4X4 Torque King mainshaft. On the other hand, this post seems to indicate a Standard Trans fully splined shaft wasn't so bad after all ( https://www.turbodieselregister.com...orque-king-4500-transmission-who-has-one.html ) so now I'm kinda confused.



I'm leaning towards an exchanged NV 4500 rebuild by Blumenthal or Standard including the upgraded mainshaft at less than half the cost of a new one by Quad 4X4 with the Torque King shaft. No slam on Quad 4X4, but I'm going to a 13" clutch at the same time and cost is a factor for me.



I'd appreciate any advice from those who have been down this road before.

 

[hsmith]

Very common, even on un-modded engines. You can remove the tail housing, clean things a bit and reinstall the fifth gear nut with loctite. Hammer it real tight. Will buy you quite a bit of time. No need to replace the transmission for this problem.
Or, remove it and have the fully splined shaft installed.

 

[CumminsPower98]

Mine fell off at 91,405. I got the truck with 67k in stock form so it didn't have a lot of miles with my power enhancements. I put the thing back together and ran it for about 6k miles before I upgraded to an NV5600.



I agree that you could put it back and buy some time if you wanted to save and do something better later. All you have to do is pull the tail housing off with trany while still in the truck to make the repair. It helps to have the shaft holding socket and nut wrench. I bought these two tools when I did mine along with the latest nut design at the time. I put the gear on with lots of red loctite in the splines and soaked the nut threads. I torqued the nut and staked the outside lip all around with a punch (about 10 spots I think). Some pictures at the top of this page: Picasa Web Albums - Mark - Truck Stuff



I tore the trany down after the upgrade and that nut/gear was VERY hard to get off so it probably would have run for some time.

 

[WDaniels]

When I bought my new 96 3500 I got less than 12k on the transmission before the 5 gear nut fell off. Go and buy the new nut and put that one on instead of using the old nut. The new nut is put on the same as the old one except it has two cap screws that connect the halves that you tighten with an allen wrench as well. After mine was replaced with the new unit I pulled heavy loads with it up from the lower 48 all the time. On two occasions the whole rig, over the scales exceeded 37k pounds coming up through British Columbia and all its mountains and worked excellent.

WD

 

[TurboSandman]

I appreciate the opinions given for intruck repair of the 5th gear nut, but I'm planning to yank the transmission anyway to do the clutch; I just started another thread on that https://www.turbodieselregister.com...el-options-13-clutch-upgrade.html#post2088829

I was wondering more about whether the Torque King mainshaft was that much of a better fix than the fully splined mainshaft sold by Blumenthal and Standard Trans. I did some price checking and I can exchange for a rebuilt transmission by Blumenthal which includes the upgrade at a reasonable cost, but I wanted to know if this upgrade failed that much earlier than the Torque King. Anyone have experience with this?

I doubt I'll ever go with twins or so any pulling, so I'm thinking the bigger input shaft would be wasted on me; anything else I should consider?

 

[Extreme1]

Don't drive too far as it is. I had a friend do that and the junk in the oil wrecked most of the trans parts. That might cost you when you send it in as a core.

 

[WDaniels]

Turbo,

Look into Quad 4X4's kits. They are in Montana. Their service is as good as it gets and his kits, of which there are several to choose from, are top notch. I've never rebuilt a transmission before but got his book and a couple of tools and redid mine. Outstanding kit and business.

I'm not affiliated in any way with Quad but their service and parts are second to none.

WD