ATF leak

Clutch, transmission, rear axle

Moderators: FORDification, 70_F100

Post Reply
goat_72
New Member
New Member
Posts: 18
Joined: Sun Oct 01, 2017 1:44 am

ATF leak

Post by goat_72 »

Today I took my 72 F100 with a FE 390 C6 Auto to Jiffy Lube for an oil change. I have seen since buying the vehicle in the fall of 2017 that there has been a small leak, mostly ATF. On checking the fluids, ATF was definitely low.

We tracked down the leak to two places, one the driver side where the linkage to the shifter is and then more prominent leak being on the connector between main shaft and transmission. The chap at Jiffy, suggested it is a rubber seal of sorts and fairly easy fix, but requires to take the shaft out.

Pic attached of the part in question. Considering this is dismantling of the shaft from the transmission, I suspect it's a good opportunity to do take care of others things perhaps on the other side of by the differential.

Subject to keep an eye on ATF levels, how urgently / or worried should I be in prioritizing this fix. I am toying with doing it myself, or taking it to a shop. As you can probably tell, this is not my primary skill set. None the less willing to give it go.

Last stupid question, what is the correct terminology for these transmission anatomies :-D ??

Thanks.
GOAT_72
IMG_0316.JPG
You do not have the required permissions to view the files attached to this post.
'72 f100 swb
'17 audi allroad
'15 toyota highlander
wife & 2 kids
Bill Ramsey
Preferred User
Preferred User
Posts: 253
Joined: Tue Sep 03, 2013 7:01 pm
Location: San Diego

Re: ATF leak

Post by Bill Ramsey »

output shaft seal. easy to do if you know how and have the tools.

my bigger concern is asking the guy at jiffy lube for advise. they were not thinking of oil changes when they named that place.
1968 Highboy
1976 Highboy
1969 F250 Camper Special
1941 Dodge Power Wagon
1930 Model A Coupe (Hotrod)
1962 Fairlane 500 Sports Coupe
VW Sandrails
Honda ATC's
36' Diesel Pusher for roughing it.
User avatar
Jacksdad
Blue Oval Fan
Blue Oval Fan
Posts: 579
Joined: Sat Mar 30, 2013 8:52 pm
Location: San Diego, CA

Re: ATF leak

Post by Jacksdad »

Bill Ramsey wrote: my bigger concern is asking the guy at jiffy lube for advise. they were not thinking of oil changes when they named that place.
Exactly right. They don't make any money giving advice, and a seal change can easily turn into a transmission rebuild once it's up on a lift and torn down. Ask me how I know...
1971 DRW F350 cab and chassis with an Open Road motorhome conversion, Dana 70, 352 (originally 390)/C6, PS, power front discs, and 159" w/b.
User avatar
DuckRyder
Moderator
Moderator
Posts: 4893
Joined: Mon Jul 19, 2004 3:04 pm
Location: Scruffy City
Contact:

Re: ATF leak

Post by DuckRyder »

It is a long bed with a 2pc driveshaft right?

Speedometer gear adapter looks suspect too, I would clean it all off and keep an eye on it...
Robert
1972 F100 Ranger XLT (445/C6/9” 3.50 Truetrac)

"An unarmed man can only flee from evil, and evil is not overcome by fleeing from it." -- Jeff Cooper
goat_72
New Member
New Member
Posts: 18
Joined: Sun Oct 01, 2017 1:44 am

Re: ATF leak

Post by goat_72 »

Hi

@jacksdad - the dude at Jiffy wasn't suggesting they would fix it just to be clear, but helped track down the leak itself. I am debating wether this is something I do myself or get someone (i trust) to do it.

@duckryder - no this is a swb. as for the speedometer gear adaptor, are you referring to the two cables rubbing or the apparent degradation of the horizontal cable - aka I presume this is the speedo cable?

I suspect you guys telling me to get this into a reputable transmission / mechanic shop?
'72 f100 swb
'17 audi allroad
'15 toyota highlander
wife & 2 kids
User avatar
DuckRyder
Moderator
Moderator
Posts: 4893
Joined: Mon Jul 19, 2004 3:04 pm
Location: Scruffy City
Contact:

Re: ATF leak

Post by DuckRyder »

It should not be hard if you have some mechanical skill and we can help you too.

The speedometer cable is the one going into the transmission, it screws on to an adapter that is held in by the bolt below it in the retainer. There is a seal (an O ring) on it.

I was under the impression that short beds had a slip yoke in the transmission tail shaft but that looks like a bolt on yoke on the back of the trans (is there a huge nut in the center of it)

In anycase, If you do change the tail seal, you will probably want to have a seal saver onhand (it is a sleeve that will go over the surface of the yoke and give a smooth surface for the seal to ride on if there are groves worn into the yoke).
Robert
1972 F100 Ranger XLT (445/C6/9” 3.50 Truetrac)

"An unarmed man can only flee from evil, and evil is not overcome by fleeing from it." -- Jeff Cooper
Post Reply