Looking for help replacing all rear diff seals & brake shoes AND diagnosing issue
01-02-2017, 06:24 PM
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Looking for help replacing all rear diff seals & brake shoes AND diagnosing issue
I've got a 99 4Runner, V6, 5 speed, 4wd, 216k miles
The rear differential is leaking about a 1/4 qt oil a week from the pumpkin in the center AND both axle seals, there is splatter all on the inside of both the rear wheels.
I got a quote from a reliable shop and they said to do it right, which might mean replacing bearings and doing some trickery so those axle seals stay sealed, $2100-3500. I paid $4500 for the truck just over a year ago.
Recently I had all the work and satisfaction of tracing a bad noise and vibration to a mangled double cardan joint on the driveshaft and was fortunate to find a pristine replacement at a local pick and pull. Now this differential repair looks like its going to be up to me to address and to be bluntly honest, I'm burnt out on scouring forums and youtube to teach me what I've got to do.
I need to replace all the seals in my rear differential and axles, replace the brake shoes and clean the drums which I was told will be covered in the oil from the splatter, and be able to diagnose any other issues going on to prevent the seals from failing again.
If anyone has any previous forum threads, write-ups, videos, or diagrams about differential seal replacement, diagnostics, and brake shoe replacements I am super grateful for any help in pointing me in the right direction. Also the rear differential fill plug rounded over when I tried getting it off. I had to weld a 3/4" nut to it just to break it free and refill the gear oil. Anyone know how I can search for or where I can get a new fill plug?
Thanks
The rear differential is leaking about a 1/4 qt oil a week from the pumpkin in the center AND both axle seals, there is splatter all on the inside of both the rear wheels.
I got a quote from a reliable shop and they said to do it right, which might mean replacing bearings and doing some trickery so those axle seals stay sealed, $2100-3500. I paid $4500 for the truck just over a year ago.
Recently I had all the work and satisfaction of tracing a bad noise and vibration to a mangled double cardan joint on the driveshaft and was fortunate to find a pristine replacement at a local pick and pull. Now this differential repair looks like its going to be up to me to address and to be bluntly honest, I'm burnt out on scouring forums and youtube to teach me what I've got to do.
I need to replace all the seals in my rear differential and axles, replace the brake shoes and clean the drums which I was told will be covered in the oil from the splatter, and be able to diagnose any other issues going on to prevent the seals from failing again.
If anyone has any previous forum threads, write-ups, videos, or diagrams about differential seal replacement, diagnostics, and brake shoe replacements I am super grateful for any help in pointing me in the right direction. Also the rear differential fill plug rounded over when I tried getting it off. I had to weld a 3/4" nut to it just to break it free and refill the gear oil. Anyone know how I can search for or where I can get a new fill plug?
Thanks
01-02-2017, 11:44 PM
#2
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99% of the time an axle leak on the Toyota's is caused by poorly located blocked air Vent, you need to check it every 6 months from my experience, or relocate it to the gas cap and never worry about it again.
I ground the bearings off the axle but you don't want to grind into the axle shaft or seal surface so you better be really good with a grinder and have a keen eye, you will need factory bearing$$, inner and outer seals, new brake shoes and 3 or 4 cans of brake clean. I also had a groove in the inner sealing surface of the axle and installed the seal 1mm out from factory so the seal would ride on a nice new surface.
I grind down the 24mm socket face so it grabs more of the shallow diff plugs commonly found to avoid rounding them and always start with the fill plug first, the drain & fill plugs and gaskets are available at Toyota as they are still the same in 2017.
Not sure where the pumpkin is leaking but if it is rusted out (very common in the salt belt) you might want to look to see if that donor at the wreckers has the same ratio/options and low miles, then buy the entire differential if yours is leaking from the diff housing due to rust causing pin holes as there is no other fix except bandaid fixes for rusty diff housings (although JB weld works after polishing it). Its not hard to pull the entire axle, probably just as much labour. Don't forget to grease the centre of the double cardan joint, and u-joints every oil change, and only 1 pump in the slip joints.
No write up but its all self explanatory once you start wrenching whichever route you go, there was a recent discussion about axle seals leaks here last year, but its all about the vent, seal location, and bearing quality.
I ground the bearings off the axle but you don't want to grind into the axle shaft or seal surface so you better be really good with a grinder and have a keen eye, you will need factory bearing$$, inner and outer seals, new brake shoes and 3 or 4 cans of brake clean. I also had a groove in the inner sealing surface of the axle and installed the seal 1mm out from factory so the seal would ride on a nice new surface.
I grind down the 24mm socket face so it grabs more of the shallow diff plugs commonly found to avoid rounding them and always start with the fill plug first, the drain & fill plugs and gaskets are available at Toyota as they are still the same in 2017.
Not sure where the pumpkin is leaking but if it is rusted out (very common in the salt belt) you might want to look to see if that donor at the wreckers has the same ratio/options and low miles, then buy the entire differential if yours is leaking from the diff housing due to rust causing pin holes as there is no other fix except bandaid fixes for rusty diff housings (although JB weld works after polishing it). Its not hard to pull the entire axle, probably just as much labour. Don't forget to grease the centre of the double cardan joint, and u-joints every oil change, and only 1 pump in the slip joints.
No write up but its all self explanatory once you start wrenching whichever route you go, there was a recent discussion about axle seals leaks here last year, but its all about the vent, seal location, and bearing quality.
01-03-2017, 03:06 PM
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99% of the time an axle leak on the Toyota's is caused by poorly located blocked air Vent, you need to check it every 6 months from my experience, or relocate it to the gas cap and never worry about it again.
I ground the bearings off the axle but you don't want to grind into the axle shaft or seal surface so you better be really good with a grinder and have a keen eye, you will need factory bearing$$, inner and outer seals, new brake shoes and 3 or 4 cans of brake clean. I also had a groove in the inner sealing surface of the axle and installed the seal 1mm out from factory so the seal would ride on a nice new surface.
I grind down the 24mm socket face so it grabs more of the shallow diff plugs commonly found to avoid rounding them and always start with the fill plug first, the drain & fill plugs and gaskets are available at Toyota as they are still the same in 2017.
Not sure where the pumpkin is leaking but if it is rusted out (very common in the salt belt) you might want to look to see if that donor at the wreckers has the same ratio/options and low miles, then buy the entire differential if yours is leaking from the diff housing due to rust causing pin holes as there is no other fix except bandaid fixes for rusty diff housings (although JB weld works after polishing it). Its not hard to pull the entire axle, probably just as much labour. Don't forget to grease the centre of the double cardan joint, and u-joints every oil change, and only 1 pump in the slip joints.
No write up but its all self explanatory once you start wrenching whichever route you go, there was a recent discussion about axle seals leaks here last year, but its all about the vent, seal location, and bearing quality.
I ground the bearings off the axle but you don't want to grind into the axle shaft or seal surface so you better be really good with a grinder and have a keen eye, you will need factory bearing$$, inner and outer seals, new brake shoes and 3 or 4 cans of brake clean. I also had a groove in the inner sealing surface of the axle and installed the seal 1mm out from factory so the seal would ride on a nice new surface.
I grind down the 24mm socket face so it grabs more of the shallow diff plugs commonly found to avoid rounding them and always start with the fill plug first, the drain & fill plugs and gaskets are available at Toyota as they are still the same in 2017.
Not sure where the pumpkin is leaking but if it is rusted out (very common in the salt belt) you might want to look to see if that donor at the wreckers has the same ratio/options and low miles, then buy the entire differential if yours is leaking from the diff housing due to rust causing pin holes as there is no other fix except bandaid fixes for rusty diff housings (although JB weld works after polishing it). Its not hard to pull the entire axle, probably just as much labour. Don't forget to grease the centre of the double cardan joint, and u-joints every oil change, and only 1 pump in the slip joints.
No write up but its all self explanatory once you start wrenching whichever route you go, there was a recent discussion about axle seals leaks here last year, but its all about the vent, seal location, and bearing quality.
This truck has been in El Paso, TX almost its entire existence. There is no rust on it. Not sure that is the problem. Could I be lucky enough to have only a busted seal in the center diff too?
01-04-2017, 04:04 AM
#4
Registered User
The vent is at the top driver side of the Pumpkin, twist the cap until it becomes loose. It is likely the input seal then if your in El paso, remove the 4 bolts holding the u-joint to the rear diff flange, and then remove the large nut in the middle, slide the input shaft out and you have excess to the rear input seal.
01-04-2017, 08:50 AM
#5
here are some threads that may help with your leaking axle seals:
https://www.yotatech.com/forums/f128...4runner-76339/
https://www.yotatech.com/forums/f2/t...-seals-296313/
https://www.yotatech.com/forums/f2/3...arings-295681/
https://www.yotatech.com/forums/f2/p...-seals-253319/
https://www.yotatech.com/forums/f2/r...eather-272472/
https://www.yotatech.com/forums/f128...4runner-76339/
https://www.yotatech.com/forums/f2/t...-seals-296313/
https://www.yotatech.com/forums/f2/3...arings-295681/
https://www.yotatech.com/forums/f2/p...-seals-253319/
https://www.yotatech.com/forums/f2/r...eather-272472/
01-04-2017, 06:04 PM
#6
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The vent is at the top driver side of the Pumpkin, twist the cap until it becomes loose. It is likely the input seal then if your in El paso, remove the 4 bolts holding the u-joint to the rear diff flange, and then remove the large nut in the middle, slide the input shaft out and you have excess to the rear input seal.
01-07-2017, 05:11 AM
#7
Registered User
Crawl under the truck and look at the vent that I previously described and you'll answer your own question, often I rip the top off the vent cap discard the 1 way valve, and spring, and attach a fuel hose to it with a steel clamp and route it from there. Or you can unscrew the vent and buy a barbed nipple with the same thread.
