Help - Transmission Rear Seal Part No?

[swebster]

Does anyone have a part number (and/or source) for the rear seal in an 86' 345 - TH400 transmission?

I've been to Pep Boys and AutoZone with no luck. They each had the seal listed but a side by side comparison had different diameters on either the OD or the ID on the rubber seal. Missed NAPA by ten minutes so I'll try there in the morning but I was amazed that neither chain had a seal for such a common transmission.

Any suggestions would be appreciated.

[txbeaux]

Steven,
There are several seals that fit a thm400. Slip yoke and bolt on yoke I think take the same seal. However, rear seals rarely just start leaking on their own. Generally, a bad u-joint or carrier bearing will cause a seal to leak. Also the extension housing bushing will go bad from the same reasons. Check everything else real close for the source of your problem, otherwise your new seal will probably start leaking right away. Jim

[swebster]

Jim,
No doubt. I was under there investigating an ongoing (and increasing) whirr from the driveline. I've suspected the forward u joint or center bearing for quite some time and this was the weekend to tackle it.

Once under there I (re)noticed the wet drive shaft brake drum and decided to open her up. My first center bearing is pretty loose. Replacing both tomorrow.

[txbeaux]

Go with the Spicer brand. They are only slightly more and are super heavy duty. All else is lightweight and will fail you at the most inoptune time. I spent most of my working days in a Transmission Shop. Sold out 10 years ago and moved back to the country. I wouldn't put anything else in a HD application and they never came back. Good Stuff...Watch those knuckles!!! Jim

[jim8860]

Try this number NATIONAL #9449 . That number fits all 1980-1989 turbo 400 . Good luck

[jim8860]

Originally posted by swebster@myrvadvanta
Jim,
No doubt. I was under there investigating an ongoing (and increasing) whirr from the driveline. I've suspected the forward u joint or center bearing for quite some time and this was the weekend to tackle it.

Once under there I (re)noticed the wet drive shaft brake drum and decided to open here up. My first center bearing is pretty loose. Replacing both tomorrow.

I found some more info. Part number for the center bearing and u joints

MOTOR HOME CHASSIS
P318 w/178" WB w/REAR DRUM BRAKES

Drive Shaft Joint Federal-Mogul p#330 yr: 85-87

Joint
USE ON STEERING SHAFTS
w/REPLACEABLE U-JOINTS Federal-Mogul p# 338 yr:85-87

Strap Kit
FITS JOINT #330 Federal-Mogul p#492-10 yr:85-89

U-Bolt Kit
FITS JOINT #330 Federal-Mogul p#330-10 yr:85-89

Center Support
w/1.3780/1.3775 BRG INSIDE DIA Federal-Mogul p# 9845 yr: 68-89

[59toaster]

Is there no number on it? Usualy a part number is in one of the rubber lips.

I agree about going with the real Dana Spicer parts. The Chinese and Japanese rubber products stink. The US manufactured part is far superior. Look on the actual part and make sure it has Made in the USA on it. I am finding Spcer is sourcing from overseas on some parts these days.

[swebster]

there is a part number on the seal but we've not been able to xref it to anything yet. I'll be sure and ask for Dana/Spicer - good advice on that.

jim8860 - thanks for looking up all of those numbers. One thing - where did you find them? The reason I ask is that I have rear disk brakes which I've found can have different drive-train parts than the rear drums.

[swebster]

Found the seal. Slightly different depth (deeper) but fits perfectly and gives the shaft itself a wider footprint on the seal. It wasn't a Dana but it made in the UDS and was 4X the cost of the cheapo seals.

OK...next question. I've re-assembled the driveshaft brake and with the yoke bolt (through the brake drum and shaft and into the output shaft on the tranny) torqued down there's about 1/8" - 1/4" forward and backward movement on the brake drum and shaft. I suspect the bolt has bottomed out and the washer does not provide enough of a spacer to firmly hold the drum. So...is this movement normal?

I've replaced the forward U - joint and am on the hunt for a replacement (forward) center bearing (which was super sloppy upon inspection) so before I bolt everything back together I wanted to make sure this brake drum thing is good to go.

BTW - I "think" the center bearing is as follows: BCA Part # HB88107A (Ball Bearing) Bearing & Support; SPicer 1280, 1310, 13301 1410 Series / Brg. I.D. 1.3780" (35mm) - End Yoke Style (RWD) - any opinions on this one?