• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

Need some help with GearVendors OD unit behind 4L80E

You could theoretically mount a temp sensor in either the fill or drain plugs. Just take either plug to a decent hardware store that has a way to identify threads and find a plug that can be drilled/ tapped or is already threaded for 1/8" npt as that's the common trans temp probe size

I run the Tribodyn 75-90 gear oil in my front and rear diffs and in the final drives on my mini excavator. Pricey compared to standard off the shelf stuff but when compared side by side after draining my final drive motors the Tribodyn looked exactly the same as when it went in and the grey mobil gear oil was diesel black.
 
Twisted Steel Performance said:
I do understand the why...

So, @dbrannon79 what mileage increase did you get, and at 70mph what rpm are you running? What were your egt and coolant temps?
Click to expand...
I bought the truck with it installed so I don't know what it was getting before. I did the first mileage on it since getting it on the road and got 15.6 mpg. at 70 the display on the TCI tcu is reading 1800. the gauge tach is reading 2k. not sure which is more accurate but the TCI is reading raw from the front crank sensor.

I don't have an EGT installed. not running much boost on it ether uphill acceleration the most boost I have seen on the gauge is 6psi. I have the turbomaster installed on the Gm turbo but don't have it turned up too much. Tire size is 245-75-16 P series tires that are not rated for this trucks weight and 4.10 rear gears

I would assume if I got some LT series tires rated for the trucks weight, and the engine was healthier with not so much blowby it would get up in the 16's to 17's for mileage.
 
I'm not sure what to think....
My 93 dually has gotten 21-22 on the highway for years now with the cruise set on 70...right now it's a nv4500.

I do know mine doesn't like to be lugged, mine still has a stock 215k motor but it doesn't have any blowby.
 
Twisted Steel Performance said:
I'm not sure what to think....
My 93 dually has gotten 21-22 on the highway for years now with the cruise set on 70...right now it's a nv4500.

I do know mine doesn't like to be lugged, mine still has a stock 215k motor but it doesn't have any blowby.
Click to expand...
You running 4:10 differential(s) ?
Here I was thinking this GV would be the perfect answer to not having to regear my truck so I could drop RPMs to about 2000 at about 75 MPH.
Guess that just will not be an option now.
 
Well that was the first mileage reading I got to take since getting the truck running. mind you that was running off 3 year old fuel that was in the tanks on top of me tinkering with the engine. I just filled up sine our trip. this mileage was our trip out to the coast and a little bit of running around I did. I got 16.7 MPG this time around.

 
ak diesel driver said:
I'm sure that nv4500 helps with the mileage
Click to expand...

Yes I'm sure it does some, I'll know a little more when I convert back to a 4l80 this summer. The tranny builder did say a multi disc converter and TCM program change will do better than a stock converter and stock tcm tune, we will see...
 
I have to say now that I have driven the two trucks I have, both with 4l80e's, one I changed the gears from 4.10 to 3.73, and this one with 4.10's and the GV unit, the 4.10 + GV (double OD) is icing on the cake. even with smaller tires than the other. (265-75 vs 245-75) the RPM's are lower on the freeway and it had more power for pulling. I never pull trailers or loads other than when I used the 95 to tow the 93 home but if I was given the choice between the two I would choose the higher gears with the GV over the lower gears without the GV.

Now that my daughter has given us a (free to her) 30' bumper pull travel trailer, once I get it tagged and ready for a camping trip, I will get to see how well both trucks will pull it!

I know if you have to buy new, spending the $$ on the GV unit will make you think about the investment and use case if it would be worth it. That by it's self is very hard to chew on!
 
I wanted to post an update since I will be needing to get some parts for this GV unit. the truck has been sitting for the better part of a month. after I pulled it in to get the AC working, I noticed a small puddle of oil in the driveway. crawling down there revealed that the electric solenoid on the GV unit has a weep hole which gear oil is slowly dripping out even when not being driven.

I checked the oil level and it was low but not by much. I topped it off, cleaned off the wet areas with some brake cleaner when I immediately found the source of the leak. If you look closely at the center of the solenoid, there is a tiny hole. this is where gear oil is actively seeping out from. the little bit you can see in the pic flowed out within seconds of spraying with brake cleaner and wiping dry.

@Will, iirc you mentioned some of the hummer guys run these GV units. would you mind asking around if they have experienced this and possibly what needs to happen to stop the leak? I'm hoping it's simply a seal or o-ring that needs replacing on the shaft of the solenoid. but I also don't want to attempt removing this solenoid not knowing if the entire unit needs to be pulled or if it can be serviced while on the truck.

IMG_5175.jpg
IMG_5176.jpg
 
I did run across this post on the oil burners forum with a photo detailing the solenoid. it looks like I might be able to remove it and replace the seals maybe?

Gear Vendor OD troubleshooting

Checked the fluid. It was low. Added about 20 oz. and then test drive. No OD. The light comes on (Green Overdrive) and off when I kick the switch, but she doesn't switch. Bad solenoid maybe?
www.oilburners.net www.oilburners.net

1717277988118.png
 
Yes you can replace the seals.
No to the hummers running it. I was saying I wish we could, but being full time 4wd presents some issues…
The real dream would be an atlas 3 speed xfer case hut instead of high, low, ultra low- it would be low/high/ overdrive.
 
I sent an email out to Gearvendors asking about a seal kit for the solenoid. I also sent the two photos to them. I just received a response this afternoon saying that the solenoid is about to fail and would be in need of replacement. $260 plus shipping. Not sure if I should attempt to pull it and at least have a look at the condition of the seals, but I am tempted to try this weekend. if they are simply neoprene o-rings, I might attempt finding some replacements before ordering a new solenoid.
 
dbrannon79 said:
I sent an email out to Gearvendors asking about a seal kit for the solenoid. I also sent the two photos to them. I just received a response this afternoon saying that the solenoid is about to fail and would be in need of replacement. $260 plus shipping. Not sure if I should attempt to pull it and at least have a look at the condition of the seals, but I am tempted to try this weekend. if they are simply neoprene o-rings, I might attempt finding some replacements before ordering a new solenoid.
Click to expand...
And so is it okay to run the GV unit in overdrive with the transmission in OD ?
 
As far as I know, I have not seen any issues yet! to me it doesn't make sense to have the GV unit if I cant use both at the same time LOL

to be honest driving this truck is like having a set of 342 gears while on the freeway, but having a granny gear on the top end. the take off is more peppy than my 95 with the 373 gears but cruises on the freeway right at 2k rpm at 70mph. this thing would float on the freeway if it had lighter springs Lol
 
Well its time I need to address this leaking solenoid on the GV unit, the truck has been sitting for a while now. I have been doing some reading on the innerwebs and found out that these GV units seem to be basically the same as a J type layland OD unit for a Triumph. Not sure what year though.

I would like to find out what make a model Triumph they came with from factory, maybe I can find a less expensive solenoid replacement. for now I plan to do the thing I'm not supposed to do.... plug that hole up on the end with some RTV I also need to see if there is a case vent on it somewhere and make sure it's clear.

I drained what was left of the oil in it (wasn't much) so I can clean and dry that area prepping it for the RTV to have a chance to stick. I was going to attempt removing the solenoid and re-oring it, but I don't have a thin 1" wrench nor do I want to take the chance of finding out it's special size o-rings that I can't easily get. it's still functioning as it is now so I don't want to break it before I can get a replacement in hand.
 
dbrannon79 said:
Well its time I need to address this leaking solenoid on the GV unit, the truck has been sitting for a while now. I have been doing some reading on the innerwebs and found out that these GV units seem to be basically the same as a J type layland OD unit for a Triumph. Not sure what year though.

I would like to find out what make a model Triumph they came with from factory, maybe I can find a less expensive solenoid replacement. for now I plan to do the thing I'm not supposed to do.... plug that hole up on the end with some RTV I also need to see if there is a case vent on it somewhere and make sure it's clear.

I drained what was left of the oil in it (wasn't much) so I can clean and dry that area prepping it for the RTV to have a chance to stick. I was going to attempt removing the solenoid and re-oring it, but I don't have a thin 1" wrench nor do I want to take the chance of finding out it's special size o-rings that I can't easily get. it's still functioning as it is now so I don't want to break it before I can get a replacement in hand.
Click to expand...
The MG solenoid could be the same.
I’m not familiar at all with the British overdrive units.
www.mgexp.com

Search : The MG Experience

MG Car Owners Club : MGB, GT, V8, Midget, MGA, MGC : Forum, Photos, Cars For Sale, Buy & Sell, Repair, Restoration, Events : FREE to join
www.mgexp.com www.mgexp.com
 
It's funny this oil leak started right after the first time I changed the fluid, before then it was fine. GV calls for 80-90 synthetic gear lube for trucks and dex III for cars on the same unit. If it was running the ATF I would be tempted to add some stop leak but with gear lube I'm not sure there is anything I could add that would swell the seals.. GV wants over $200 for a reman solenoid and won't sell the seal kit.
 
You must log in or register to reply here.
Back
Top