Front diff punching hole in oil pan

Front diff punching hole in oil pan

Postby Tegnus [OP] » September 11th 2020, 1:55am

I have a 2004 Chevy Astro AWD and I had an issue where my engine mounts basically melted... More on it here: https://www.astrosafari.com/viewtopic.p ... 0#p1560286

Anyhow I though that problem was with the mounts dropping engine too low and that caused the hole:
Image

So I patched it with jb weld and though that all is good.
Image

BUT it appears that issues still persists as diff is still punching my JB weld away and the hole is back...

I am thinking that issue might be with front diff bushings, I understand that there are 4 of them and they all appear the same - are they?
Rockauto has no stock, but this is what I found: https://www.rockauto.com/en/moreinfo.ph ... 1&jsn=1421

I also can't figure if other places have stock as some that indicate status show discontinued, and some show nothing...

Is there anything I am missing that would cause this issue, except for those 4 bushings and transmission mount are there any other parts affecting this?
Also any suggestions for alternate parts just in case I can't find OEM?


Also will probably replace transmission mount as that has probably been shot too, why wouldn't it if everything else is not looking great... :banana:
2004 Astro AWD (Astrid), 3" Lift, BFG All-Terrain T/A KO2 LT225/75R16, Tru-Cool LPD-4490 Trans cooler, ARB Awning 2500 (ARB4401A)

Follow us on Facebook and Instagram | Check out the build of our 2004 Chevy Astro AWD "Astrid"
Original Poster [OP]
User avatar
Tegnus
Firing on 5 Cylinders (L1)
Firing on 5 Cylinders (L1)
Years of Membership: Tegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full years
Posts: 532
Topics: 38
Images: 6
Joined: April 2013
Location: Canada/Latvia
Gender: Male
Alias (AKA):
Van Model Year: 2004
Van Make/Model: Chevrolet Astro
Extra Info: AWD

  • Similar topics
    Replies
    Views
    Author
  • Replacing engine sump/oil pan
    by Wokka » October 18th 2020, 8:41pm in Engines
    2 Replies
    156 Views
    Last post by AstroWill View the latest post
    October 19th 2020, 2:16pm
  • Non LS V8 4x4 or AWD oil pan
    by markmitch » October 23rd 2020, 12:48am in V8 Swap
    4 Replies
    358 Views
    Last post by markmitch View the latest post
    November 27th 2020, 6:15pm
  •  
    10
    35
    Last post by AstroSafari.com View the latest post
    January 17th 2021, 7:48am

Re: Front diff punching hole in oil pan

Postby MechBob » September 11th 2020, 5:02pm

Looks like you have a motor mount problem,or trans mount has been shimmed up,forcing front of engine down,or something is really bent.
User avatar
MechBob
Firing on 2 Cylinders (L2)
Firing on 2 Cylinders (L2)
Years of Membership: MechBob has been a member for 2 full yearsMechBob has been a member for 2 full years
Posts: 1257
Topics: 11
Images: 12
Joined: August 2018
Gender: Male
Alias (AKA): Bob
Van Model Year: 1994
Van Make/Model: Chevrolet Astro
Extra Info: 4x4

Re: Front diff punching hole in oil pan

Postby Tegnus [OP] » September 11th 2020, 7:47pm

MechBob wrote:Looks like you have a motor mount problem,or trans mount has been shimmed up,forcing front of engine down,or something is really bent.

So you think it has nothing to do with front diff bushings?
2004 Astro AWD (Astrid), 3" Lift, BFG All-Terrain T/A KO2 LT225/75R16, Tru-Cool LPD-4490 Trans cooler, ARB Awning 2500 (ARB4401A)

Follow us on Facebook and Instagram | Check out the build of our 2004 Chevy Astro AWD "Astrid"
Original Poster [OP]
User avatar
Tegnus
Firing on 5 Cylinders (L1)
Firing on 5 Cylinders (L1)
Years of Membership: Tegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full years
Posts: 532
Topics: 38
Images: 6
Joined: April 2013
Location: Canada/Latvia
Gender: Male
Alias (AKA):
Van Model Year: 2004
Van Make/Model: Chevrolet Astro
Extra Info: AWD

Re: Front diff punching hole in oil pan

Postby Mmusicman » September 11th 2020, 8:35pm

When my mounts were shot... my oil pan was rubbing on the differential axle tube.
But I don't recall seeing any interference with differential bushings or bolts.
Image
2000 Astro LS 4x4 | NP233 | 31" LT265/70R17 Tires | 8" LIFT | 10" TOTAL
92 Chevy Astro Cargo Shorty | V8-350
http://www.CruisinSouthFlorida.com
User avatar
Mmusicman
V8 Swap Achievement
V8 Swap Achievement
Firing on 7 Cylinders (L5)
Firing on 7 Cylinders (L5)
Years of Membership: Mmusicman has been a member for 7 full yearsMmusicman has been a member for 7 full yearsMmusicman has been a member for 7 full yearsMmusicman has been a member for 7 full yearsMmusicman has been a member for 7 full yearsMmusicman has been a member for 7 full yearsMmusicman has been a member for 7 full years
Posts: 4760
Topics: 73
Images: 49
Joined: June 2013
Location: Ft. Lauderdale, Florida
Gender: Male
Alias (AKA): Scott
Van Model Year: 2000
Van Make/Model: Chevrolet Astro
Extra Info: 2000 4x4 - 92 V8-350

Re: Front diff punching hole in oil pan

Postby MechBob » September 11th 2020, 9:15pm

The front diff is in bushings,in frame mounts-2 on the left side.If the bushings were that bad,the diff would jump up and down,and make horrible noises.I would get it looked at by a good shop.
User avatar
MechBob
Firing on 2 Cylinders (L2)
Firing on 2 Cylinders (L2)
Years of Membership: MechBob has been a member for 2 full yearsMechBob has been a member for 2 full years
Posts: 1257
Topics: 11
Images: 12
Joined: August 2018
Gender: Male
Alias (AKA): Bob
Van Model Year: 1994
Van Make/Model: Chevrolet Astro
Extra Info: 4x4

Re: Front diff punching hole in oil pan

Postby Tegnus [OP] » September 12th 2020, 2:17am

Mmusicman wrote:When my mounts were shot... my oil pan was rubbing on the differential axle tube.
But I don't recall seeing any interference with differential bushings or bolts.

Yup that was happened too, and from what I can tell after changing melted energy suspension mounts that's not happening anymore.

But it also did rub out a hole in pan, and it's still taking out jb weld even if I re-apply it.
2004 Astro AWD (Astrid), 3" Lift, BFG All-Terrain T/A KO2 LT225/75R16, Tru-Cool LPD-4490 Trans cooler, ARB Awning 2500 (ARB4401A)

Follow us on Facebook and Instagram | Check out the build of our 2004 Chevy Astro AWD "Astrid"
Original Poster [OP]
User avatar
Tegnus
Firing on 5 Cylinders (L1)
Firing on 5 Cylinders (L1)
Years of Membership: Tegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full years
Posts: 532
Topics: 38
Images: 6
Joined: April 2013
Location: Canada/Latvia
Gender: Male
Alias (AKA):
Van Model Year: 2004
Van Make/Model: Chevrolet Astro
Extra Info: AWD

Re: Front diff punching hole in oil pan

Postby MechBob » September 12th 2020, 2:58am

I will delve on this a bit more.Astros and S10/blazer deviants, have had this issue for years,mounts die, oil pan rests on axle tube,sometimes oil pan gets rubbed through.Many websites, you can research it.As we all know, original mounts for a AWD no longer exist.The "inserts(urethane) are generic,and fit many models of GM vehicles.For some years,Prothane Astro mounts were only for 2WD, whereas Energy Suspension sold different mounts,for AWD.Energy Suspension parts were/are made by Prothane.They might even be the same company,now.We do know factory,and Prothane 2WD mounts were 1/2" lower than AWD factory mounts, which is probably why Prothane never sold AWD mounts,but ES did.(the same in 2WD vs AWD s10 stuff).I noticed doing internet searches for ES, or Prothane, they started coming up with the same part numbers.Did Prothane absorb ES, and the crossover is leading to wrong part numbers/dimensions? I do not know,just throwing this out there.I will also say I crawled under my 96 astro AWD,in the gravel, it has well over 200k, original engine mounts.and the distance from the oil pan to the "black" steel tube that is the right axle carrier, is 3/4" or a bit more.And,the distance of the pan from the axle tube to the bolt(in your pictures,that holds on the right axle tube) is at least 3/4". Food for thought.I also could tell you about .All aftermarket motor mounts for Astro vans are now back to using the same mounts that fit S10's, 1/2 and larger pickup trucks,again.Is because they are old.They work,they just might not work properly.or for a long time.But,in your case, seems might be something else going on.
User avatar
MechBob
Firing on 2 Cylinders (L2)
Firing on 2 Cylinders (L2)
Years of Membership: MechBob has been a member for 2 full yearsMechBob has been a member for 2 full years
Posts: 1257
Topics: 11
Images: 12
Joined: August 2018
Gender: Male
Alias (AKA): Bob
Van Model Year: 1994
Van Make/Model: Chevrolet Astro
Extra Info: 4x4

Re: Front diff punching hole in oil pan

Postby SportsBoy » September 15th 2020, 12:20am

I'm pretty sure this is a poly replacement for the diff bushings -
https://www.amazon.com/gp/product/B000CNAXAW/ref=ox_sc_saved_title_2?smid=ATVPDKIKX0DER&psc=1
Image
User avatar
SportsBoy
Firing on 5 Cylinders (L1)
Firing on 5 Cylinders (L1)
Years of Membership: SportsBoy has been a member for 3 full yearsSportsBoy has been a member for 3 full yearsSportsBoy has been a member for 3 full years
Posts: 597
Topics: 21
Images: 23
Joined: August 2017
Location: Massachusetts
Gender: Male
Alias (AKA): Blake
Van Model Year: 1997
Van Make/Model: GMC Safari
Extra Info: 4.3 AWD

Re: Front diff punching hole in oil pan

Postby Tegnus [OP] » September 21st 2020, 7:53pm

MechBob wrote:I will delve on this a bit more.Astros and S10/blazer deviants, have had this issue for years,mounts die, oil pan rests on axle tube,sometimes oil pan gets rubbed through.Many websites, you can research it.As we all know, original mounts for a AWD no longer exist.The "inserts(urethane) are generic,and fit many models of GM vehicles.For some years,Prothane Astro mounts were only for 2WD, whereas Energy Suspension sold different mounts,for AWD.Energy Suspension parts were/are made by Prothane.They might even be the same company,now.We do know factory,and Prothane 2WD mounts were 1/2" lower than AWD factory mounts, which is probably why Prothane never sold AWD mounts,but ES did.(the same in 2WD vs AWD s10 stuff).I noticed doing internet searches for ES, or Prothane, they started coming up with the same part numbers.Did Prothane absorb ES, and the crossover is leading to wrong part numbers/dimensions? I do not know,just throwing this out there.I will also say I crawled under my 96 astro AWD,in the gravel, it has well over 200k, original engine mounts.and the distance from the oil pan to the "black" steel tube that is the right axle carrier, is 3/4" or a bit more.And,the distance of the pan from the axle tube to the bolt(in your pictures,that holds on the right axle tube) is at least 3/4". Food for thought.I also could tell you about .All aftermarket motor mounts for Astro vans are now back to using the same mounts that fit S10's, 1/2 and larger pickup trucks,again.Is because they are old.They work,they just might not work properly.or for a long time.But,in your case, seems might be something else going on.

Thank you for background info. I have had poly engine bushings (same p/n) for ~6-7 years, but for whatever reason they only broke trough oil pan this year. I assume they might have been hitting oil pan before, but as mounts melted (catalytic converter failed last year), they dropped even more and that little bit was enough to rub out hole and JB weld is not strong enough to withstand occasional hit from diff, where oil pan without holes would be ok.

I have source original diff bushings, will probably swap out oil pan for a new/used without holes and change transmission mount and see if that makes any difference. Will probably know that at the end of winter as this is most likely not a project I'll take on this year. I have Tacoma as "daily" (weekend) driver so it kind of fill hole especially now when long term camping season is coming closer to end and I can do couple nights easily in tent.
2004 Astro AWD (Astrid), 3" Lift, BFG All-Terrain T/A KO2 LT225/75R16, Tru-Cool LPD-4490 Trans cooler, ARB Awning 2500 (ARB4401A)

Follow us on Facebook and Instagram | Check out the build of our 2004 Chevy Astro AWD "Astrid"
Original Poster [OP]
User avatar
Tegnus
Firing on 5 Cylinders (L1)
Firing on 5 Cylinders (L1)
Years of Membership: Tegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full years
Posts: 532
Topics: 38
Images: 6
Joined: April 2013
Location: Canada/Latvia
Gender: Male
Alias (AKA):
Van Model Year: 2004
Van Make/Model: Chevrolet Astro
Extra Info: AWD

Re: Front diff punching hole in oil pan

Postby Tegnus [OP] » January 11th 2021, 10:40pm

So I went ahead and swapped out oil pan and transmission mount mid-December and went for a 1200 mile/2000km test drive/Christmas camping trip to Rockies. Had a great time and after returning home decided to look underneath - looking good so far. We didn't do any 4x4 action really, barely left pavement - lots of snow up there so not much FSR exploring, but yeah, I am happy there isn't a new hole in engine and hopefully this lasts at least another 5-7 years (if we still have Astrid by then).

Image

As you can see it's still touched oil pan, but at least oil pan is not leaning on diff all the time, which happened before the last hole occurred.
2004 Astro AWD (Astrid), 3" Lift, BFG All-Terrain T/A KO2 LT225/75R16, Tru-Cool LPD-4490 Trans cooler, ARB Awning 2500 (ARB4401A)

Follow us on Facebook and Instagram | Check out the build of our 2004 Chevy Astro AWD "Astrid"
Original Poster [OP]
User avatar
Tegnus
Firing on 5 Cylinders (L1)
Firing on 5 Cylinders (L1)
Years of Membership: Tegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full yearsTegnus has been a member for 7 full years
Posts: 532
Topics: 38
Images: 6
Joined: April 2013
Location: Canada/Latvia
Gender: Male
Alias (AKA):
Van Model Year: 2004
Van Make/Model: Chevrolet Astro
Extra Info: AWD


 
  • Related topics
    Replies
    Views
    Last post

Return to 4WD,AWD And Transfer Case

It is currently January 17th 2021, 7:48am

Recent Image Attachments
Views: 134
Comments: 5
Date: Jan 10 '21
Time: 5:26pm
» Read last comment
Views: 134
Comments: 5
Date: Jan 10 '21
Time: 4:31pm
» Read last comment
Views: 2585
Comments: 52
Date: Jan 09 '21
Time: 5:18pm
» Read last comment
Views: 134
Comments: 5
Date: Jan 05 '21
Time: 11:22pm
» Read last comment
Views: 117
Comments: 2
Date: Dec 12 '20
Time: 4:25pm
» Read last comment
Sponsors

Who is online

Users browsing this forum: No registered users and 5 guests