transfer case overfilled with gear oil?

[topherbecker]

Just finished my first long trip in the 62. DC to Cleveland. Was pleasantly surprised to average 16mpg door to door (up from 11 in mixed city/hwy driving).

Noticed an odor of gear oil when i got to my destination, and also the hatch glass has a very light coating of oil. I knew already i had a leak, so thought i'd check the tcase to see if it needed topping up. to my surprise it was overfilled pretty significantly. see pics. i'd say there is about 14-16 ounces too much. also the color was pretty black. I THINK this is all gear oil (i.e. not contaminated with ATF); it smells like s*** and has no reddish hue to it. i'm too inexperienced to tell based on viscosity though. It's not wattery, but it's not really thick either - i'd say about the consistency of 10W (cold). few questions for this newb.

1) Did I use the correct bolt to check the level? In the pic it's the one behind that corrugated metal hose cover. You can just see it facing to the right (rear of truck) of the pic.
2) How do I know if it's ATF mixing in? Continue to check? assuming it is ATF coming in, it will continue to overfill, and eventually turn red, right?
3) is it possible PO over filled by that large an amount? I'm thinking if it was filled on an incline, it could be possible.
4) Am I okay to make the drive back to DC with this issue? It's 380 miles. Anything I should keep in mind on my trip? Things to check or monitor along the way?

thanks for your help.

-b

 

[Benjaman]

I hear the seal can leak between the trans and transfer. I'd change both and check it in a week.

Just finished my first long trip in the 62. DC to Cleveland. Was pleasantly surprised to average 16mpg door to door (up from 11 in mixed city/hwy driving).

Noticed an odor of gear oil when i got to my destination, and also the hatch glass has a very light coating of oil. I knew already i had a leak, so thought i'd check the tcase to see if it needed topping up. to my surprise it was overfilled pretty significantly. see pics. i'd say there is about 14-16 ounces too much. also the color was pretty black. I THINK this is all gear oil (i.e. not contaminated with ATF); it smells like s*** and has no reddish hue to it. i'm too inexperienced to tell based on viscosity though. It's not wattery, but it's not really thick either - i'd say about the consistency of 10W (cold). few questions for this newb.

1) Did I use the correct bolt to check the level? In the pic it's the one behind that corrugated metal hose cover. You can just see it facing to the right (rear of truck) of the pic.
2) How do I know if it's ATF mixing in? Continue to check? assuming it is ATF coming in, it will continue to overfill, and eventually turn red, right?
3) is it possible PO over filled by that large an amount? I'm thinking if it was filled on an incline, it could be possible.
4) Am I okay to make the drive back to DC with this issue? It's 380 miles. Anything I should keep in mind on my trip? Things to check or monitor along the way?

thanks for your help.

-b

 

[Kynot62]

Your pics didn't come through.

Did oil come pouring out the fill hole? Its just to the left of the idler shaft on the back of the case. Idler shaft is the one with the small bolt and usually a ground wire attached. Your description sounds like the correct fill hole.

Odd that there would be so much excess as its virtually impossible to overfill. Could be getting ATF through the seal but not very likely, usually when the seal between the auto and the tcase fails it pumps 90 wt into the tranny. Check the tranny fluid. Was the extra oil foamy? That could account for the extra. And it could have been too light of an oil.

Drain and refill your tcase to the proper level with 90 wt and you should be fine driving home. Check it when you get home, if it is leaking ATF into the tcase it took thousands of miles to get there. The seal between the tcase and tranny is not a simple fix, requires disassembly of the tcase.

Are you sure that the oil on the hatch is gear oil, Not ATF? And yes old 90 wt smells horrible, especially if it has not been changed.

Tony

 

[2mbb]

it's got to come from some place. Either it was overfilled the last time it was filled, but it seems that you check it often. Or it's coming from the transmission, which means it's ATF. 16 ounces is 1/2 quart, which is not too bad.

I would make sure the transmission has enough fluid and drive it home. Then once home, drain and fill both and closely monitor.

 

[topherbecker]

Your pics didn't come through.

Did oil come pouring out the fill hole? Its just to the left of the idler shaft on the back of the case. Idler shaft is the one with the small bolt and usually a ground wire attached. Your description sounds like the correct fill hole.

Odd that there would be so much excess as its virtually impossible to overfill. Could be getting ATF through the seal but not very likely, usually when the seal between the auto and the tcase fails it pumps 90 wt into the tranny. Check the tranny fluid. Was the extra oil foamy? That could account for the extra. And it could have been too light of an oil.

Drain and refill your tcase to the proper level with 90 wt and you should be fine driving home. Check it when you get home, if it is leaking ATF into the tcase it took thousands of miles to get there. The seal between the tcase and tranny is not a simple fix, requires disassembly of the tcase.

Are you sure that the oil on the hatch is gear oil, Not ATF? And yes old 90 wt smells horrible, especially if it has not been changed.

Tony

pics should be up now.
yup, oil came pouring out the filler hole.

i've checked the tranny fluid a few times since i purchased in january, and it looks normal (also looked okay according to my mech who pulled the dipstick before i left). i checked it after driving a 150 miles on the way here, and it looked alright. check out the attached which i snapped just now (it shows a little cleaner in the pic than what it really looks like). if there's any gear oil in there, i imagine it is a very small amount.

the oil was not foamy. see pic. this was drained after sitting overnight - the fluid was cold.

the oil on the hatch smells the same as what came out of the tcase.

i will change out the oil today - heading back home tomorrow.

thanks for the quick replies everyone.

-b

 

[Kynot62]

Post up what you find when you get home. We all learn from these odd things our rigs do.

Drive safe

Tony

 

[studawg]

Same thing happened to me, it was the seal between transmission and transfer.

 

[cruiser88]

its real common...........dont panic.

the tranny flid will not hurt the transfer

 

[gaylon]

its real common...........dont panic.

the tranny flid will not hurt the transfer

It cost me around $600 to have a dealer replace this seal. Mine failed in the middle of a long distance move and failed badly dumping lots of fluid on the ground - although I am sure it failed gently for a long time first. My first indication was the rear seal of the transfercase giving after the transmission dumped several quarts of ATF into it. This is what will happen if you ignore this for too long. I would get it fixed, or fix it quickly yourself.

 

[darthvincor]

I had the same thing, when I changed the oil on the transfer case for the first time.
It came pouring out of the filler pug, not dripping, literally pouring.

I took it to a mechanic, and he said it may have been too old and too light oil that had gotten past the seal, and he believed the original seal ought to have been replaced long ago, so it probably wasn't the seal. (according to him)

But still, I'm not so sure. I've been putting off removing the filler plug to check the oil level.

 

[topherbecker]

Well I changed out the tcase oil last night and head back to DC today. Will check the filler plug every 300 miles or so to see at what rate ATF is infiltrating.