Anyone tap a drain plug in the diff?

[fj40charles]

Today I drained and filled the rear diff with new gear oil. This is the second time I've had the cover off. Looking inside, there is a low spot in the center housing. I wonder if anyone has

drilled and tapped a NPT fitting to make their own drain plug?



I had some custom Reverse cut Dana 60 axles built for my

next offroad rig and I had drains plugs installed.



I like the idea of having a drain plug at the bottom on the diff. housing. I think it would drain better than a Mag Hytec. I'm not necessarily sold on the Mag Hytec diff cover yet... . at least not for the price. I tow about 4 times a year towing my FJ40. I figure I'm towing about 8K max with the trailer.



BTW, I'm using Amsoil series 2000 75-140W synthetic gear lube.



Comments?



Thanks in advance,

Charles

 

[Don M]

Where have you been hiding at? I have seen and heard of guys tapping the transmission for a plug, but never the Dana 80. Once you find out something, let me in on it.



Don~

 

[M Barnett]

Easy fix. I can't remember what you call them, but you can buy a round plug that is tapped for a pipe thread and all you have to do is drill a hole through the cover at the right place and weld it in. I have a lathe and make my own. Are they called bungs? Somebody will know.

Michael

 

[Speedo]

Housing drain

Dana used to put drain plugs in the bottom of the

housings but they quit around 1970, the boss is

still cast into the housing all you need to do is

drill and tap it. You should know that if you use

it off road and drag it across rocks you can

damage the plug and cause it to leak.

 

[dan_gilson]

My mag-hytec cover works good. It has a drain. It also has an easier filler as well as a dip stick to that I can tell how full it is without stinky fluid leaking out. I think the biggest advantage for you would be the doubling of the capacity. I don't have a temp gauge yet but it doubling the capacity has got to cool things down a little. The dip stick does pull metal shavings from the fluid. I checked it after coming back form the moutains and it was covered with small filings.

 

[Ted Constantine]

My 1965 land rover has drain plugs in the bottom of the housings. It makes life SO MUCH EASIER. I have thought about that on the truck but for how infrequently they need to be changed I figured it was not worth the effort of retrofitting. The rover is of course a third member axle so it has no cover to remove but the trouble of removing the covers and dealing with RTV just plain sucks.



Ted

 

[illflem]

I drilled and tapped both the front and rear differentials on a buddy's '96 with objections and no warranty from me just because I had never done it before. He liked offroading though deep water and felt the need to change fluid after each deep water experience. Said he knew others that had done it. It's been four years with no problems. Tapped 3/8" NPT threads and used hex socket plugs that are recessed and won't catch on anything. It was an easy job with a lot of fear factor, sure didn't want to mess up his diff housing.

 

[fj40charles]

My custom axles had hex plug fittings. I need to get drill and tap to do this. However, since I put new fluid in it, I'll wait until next year. I'll post pics next year if I remember to do it. .



Has anyone drilled/tapped a drain plug in the NV5600?



Having to pull the diff cover to drain the gear oil really stinks (pun intended).



Don, I'm still here. . Just laying low for now. . I can't do anything to my truck until I get a new clutch. I'm in the middle of remodeling a house and it is costing $$$$ right now.



Charles

 

[hammersley]

This doesn't weaken the housing......

Are you sure that you aren't significantly weakening the housing by drilling and taping without a corresponding design change?