TA Performance, Summit and LPW 10 Bolt Rear End Covers

F9K9 · Post by **F9K9** » Sat Sep 30, 2006 8:44 am

Anyone know anything about these differential covers?

killian96ss · Post by **killian96ss** » Sat Sep 30, 2006 9:40 am

The T/A covers are nice and are basically the same as the Summit or LPW covers with the bearing cap pre-load bolts.

Here is a picture of my Summit cover for reference.

The nice thing about the Summit cover is that it also come with ARP 12 point stainless steel bolts.

Steve

Post by **HenryJ** » Sat Sep 30, 2006 9:58 am

I like the high fill being available.
Here's the one I have:

Don't forget to file a relief for the oil passage and trim the gasket of used/required. I did not completly open the holes , but filed at approximately a 30* angle across probably 2/3 of the hole. The inside of the filed relief is probably 3/16" to 1/4" deep in the cover. This should leave an opening shaped like a "cat's eye" , maybe 1/4" wide and 1/2" tall, when bolted in place.

killian96ss · Post by **killian96ss** » Sat Sep 30, 2006 10:22 am

HenryJ wrote:I like the high fill being available.
Here's the one I have:

The high fill hole is really just there for convenience since you do not want to fill the fluid to that level. They are nice for filling diffs that have extreme pinion angles, however if you get one with a high fill hole you still want to make sure that you use the factory side differential fill hole to get the fluid to the proper level.

Brule, this info is not directed at you since I already know that you know the proper fill procedure.

I just want to make sure that other people know not to fill their diffs to the top.

Steve

F9K9 · Post by **F9K9** » Sat Sep 30, 2006 10:29 am

The T/A (free shipping) is $159. The Summit is $149.95. plus their $9.95 S&H BS. The T/A holds 1/2 pint more fluid and has a higher fill port. The only LPW I could find online is $155.95 before shipping. Beginning to look like a "no brainer" since I am very close to being fed up with Summit.

killian96ss · Post by **killian96ss** » Sat Sep 30, 2006 10:36 am

f9k9 wrote:Beginning to look like a "no brainer" since I am very close to being fed up with Summit.

I'm surprised to hear that some people have problems with Summit Racing.

I have been ordering parts from them for the past 16 years and I've never had any problems.

Maybe they are just nice to me since I have easily made them $15k-$20k richer.

Steve

F9K9 · Post by **F9K9** » Sat Sep 30, 2006 10:44 am

You just never owned a pet duck before, Steve

killian96ss · Post by **killian96ss** » Sat Sep 30, 2006 2:38 pm

f9k9 wrote:You just never owned a pet duck before, Steve

Ya, I here those ducks can be a real PITA.

Steve

Snoman002 · Post by **Snoman002** » Sat Sep 30, 2006 3:32 pm

Dang, wish they wern't so expensive, I would like one for when I put the V8 in the 91. I hear these are an excelent addition to help the relativly weak 7.6 rear end.

F9K9 · Post by **F9K9** » Sun Oct 01, 2006 9:44 pm

I decided to give Summit one more go. I gave Summit the "one more chance" routine mainly because of Steve's experiences of turning steering wheels in both directions

crew cab sonoma · Post by **crew cab sonoma** » Wed Oct 04, 2006 5:30 am

if you cant afford one of these nice aftermarket covers, but like the idea of having a drain plug,
you can modify the differential housing quite easily to allow draining the oil by simply removing the bottom cover plate bolt....

im in the process of installing a Torsen carrier in my 2000 extended cab, and while im at it, i drilled a small hole from a right angle to intersect with bottom center cover plate bolt hole.

theres a "notch" in the 7.6" housing casting to the right of this bolt hole that allows this. you only have to drill through about a quarter inch of material. i used a 15/64 drill bit, but a slightly smaller one will probably do.

you have to come in from the right (passenger) side at a fairly shallow angle, with the drill resting against the housing gasket surface, to avoid hitting and damaging the recessed bolt hole threads.

cover the ring gear and carrier with something while drilling, to avoid throwing any metal shavings into them, although drilling slowly should prevent this, do it anyway, just in case.

Q-Tip swabs dabbed in oil or grease will help in removing any hard to get at metal shavings....

you will need to use some type of sealant behind the head of the bolt, to prevent any oil seepage.
dont worry about sealing the bolt threads,, as the bolt hole is blind tapped, but it is a good idea to put some mild thread locking compound on the threads, to help ensure the bolt doesnt loosen on its own...

ill try to get a picture posted up of this in the next few days...

F9K9 · Post by **F9K9** » Wed Oct 04, 2006 1:38 pm

HenryJ wrote: Don't forget to file a relief for the oil passage and trim the gasket of used/required. I did not completly open the holes , but filed at approximately a 30* angle across probably 2/3 of the hole. The inside of the filed relief is probably 3/16" to 1/4" deep in the cover. This should leave an opening shaped like a "cat's eye" , maybe 1/4" wide and 1/2" tall, when bolted in place.

Can you give me a rough idea where I have to file to remove the metal? Will a chainsaw sharpening bit for a Dremel tool work?

Post by **HenryJ** » Wed Oct 04, 2006 1:54 pm

Wrong Differential Gasket And Cover ?

That thread should explain most of the issue.

This post should tell what I did - Differential rear-end support cover

Basically you need to cut the holes in the gasket to match the holes in the axle housing. Or go buy a gasket that has the correct holes. Then lay it on the new cover and trace the hole location. Then file a relief in the cover to allow the oil draining down the inside of the cover to be picked up and drained into those holes. A groove upward would be a good choice.

Try to mimic the relief that the stock stamped cover for the 8.5" differential cover has. The link above has a picture of it.

Leave enough meat that the gasket will seal good. Opening the hole any at all should be better than none at all.

F9K9 · Post by **F9K9** » Wed Oct 04, 2006 2:10 pm

Good Links! Thanks.

The second link provided a real treasure though

HenryJ wrote:
quickbiker wrote:...ordered this onewhich comes with a magnetic plug!

I think I like it better anyhow.
Me too, where did you get the idea that it has a magnetic plug?

BTW, you guys are costing way too much .......................................

That was two months before I bought my "money pit"

F9K9 · Post by **F9K9** » Fri Oct 06, 2006 7:01 pm

Is the white arrow pointing at one of the oiling holes in question?

Post by **HenryJ** » Sat Oct 07, 2006 5:56 am

Yes. Those allow the oil to enter the axle tubes without passing through the carrier bearings.

F9K9 · Post by **F9K9** » Sat Oct 07, 2006 6:21 am

Thanks, HJ!

Going to check my grease level one more time and give it the recommended test drive to check for leaks.

F9K9 · Post by **F9K9** » Sat Oct 07, 2006 9:49 am

One more quick question. The fill port on the Summit cover is lower than the stock fill port. That seems like an oversight to me but, I may be missing something. The stock port is above the axle tubes horizontal center. I used the stock fill port for adding new grease. Any thoughts on why Summit's fill port is lower?

Post by **HenryJ** » Sat Oct 07, 2006 10:16 am

f9k9 wrote:...The fill port on the Summit cover is lower than the stock fill port. That seems like an oversight...

It may be. It doesn't look like there was room to raise it without interfering with the logo placement.

Another thought might be that it is at oil level? The stock plug is the best location to measure the oil level. I check the level by inserting my little finger. If I can touch it with the tip when bent at the first knuckle , it is good.
The correct oil level is usually within 1/2" of the bottom of that plug.
Most think that you fill until it pours out the hole. That is not always the case.

I don't know if the "fill plug" in that rear cover would match the level 1/2" below the stock fill location?

Just an idea?

F9K9 · Post by **F9K9** » Sat Oct 07, 2006 11:19 am

HenryJ wrote:Most think that you fill until it pours out the hole. That is not always the case.

I concur and that was what I was taught when I worked at full service gas stations and at a Sears Automotive Center while I was in high school and college.

Summit wrote:Renove the fill plug. Fill the housing with proper gear oil for your application until the oil just trickles out the fill hole. This the proper fill level.

Your explanation is as good as any that I can think of. Maybe Steve will have some thoughts on this.

The cover is beefier than it appears and I tried to do a little filing and gasket cutting to provide oil flow to those axle tubes. I also decided to stick with the synthetic oil since I had already run over 17K with synthetic. It may not be the smartest thing to do but, time will tell.

I couldn't find a thread here on checking to see if. the G80 limited slip differential is working to determine if, the synthetic has affected them. My original dealership charged me for synthetic on my 3K rear differential change but, I'll keep looking.

I noticed a small amount of water contamination in the oil and rerouted my vent hose. This should be a wake up call for those that haven't checked theirs.

WVHogRider · Post by **WVHogRider** » Sat Oct 07, 2006 6:56 pm

Now you guys are going to cause me to check/change my axle/differential fluid/cover after 77K....I'll end up doing, but not yet. It will be the dead of winter....

killian96ss · Post by **killian96ss** » Thu Oct 12, 2006 5:34 am

HenryJ wrote:The correct oil level is usually within 1/2" of the bottom of that plug.
Most think that you fill until it pours out the hole. That is not always the case.

On 10 and 12 bolt chevy rear ends the correct fill level is at the bottom of the factory fill hole.

More than half of the GM repair manuals I have in my garage say to fill the diff to the bottom of the fill hole which is the same as filling it until fluid starts flowing out.

I would like point out that 2 of my manuals say that the correct fill level is 3/8" from the bottom of the fill hole.

Either way will work, but I have always filled GM rear diffs until the fluid just starts flowing out then replace the fill plug. If anything the extra oil will help keep the wheel bearings properly lubricated especially during exteme angles. Some of the newer GM diffs like on the new Silverados have a tag that says what the correct fill level is. I have also been told by a GM mechanic that rear diffs with Posi (cone or clutch type) should be filled to 3/8" below the fill hole while open diffs and gov-loc diffs should be filled to the bottom of the fill hole.

The fill hole on the 7.5" Summit cover in my opinion is too low. I would fill it through the factory fill hole until the fluid start coming out.

Here is a picture of the Summit 8.5" 10 bolt cover on my SS. Notice that the fill hole is much higher and it looks a lot like the LPW cover.

Steve

killian96ss · Post by **killian96ss** » Thu Oct 12, 2006 5:45 am

f9k9 wrote:I couldn't find a thread here on checking to see if. the G80 limited slip differential is working to determine if, the synthetic has affected them.

I have been running Redline synthetic heavy shock proof gear oil in both diffs since I purchased my CC and the gov-loc still operates just fine. I now have 88k miles on my CC.

Some people are just paranoid about synthetics or they are just too old school.

Synthetic oils are superior to convention oils in every possible way.

I run synthetic in everything except for the transmission. Automatic transmissions do not like synthetic oil.

Ask me how I know!

Steve

F9K9 · Post by **F9K9** » Thu Oct 12, 2006 7:20 am

Do you use synthetic in the transaxle?

killian96ss · Post by **killian96ss** » Thu Oct 12, 2006 8:01 am

f9k9 wrote:Do you use synthetic in the transaxle?

If you are refering to the Transfer Case then yes, I use Redline synthetic high temp ATF.

Here is a list of the synthetics that I use:

Engine - Mobil 1 synthetic 5W/30 SUV oil
Front & rear diffs - Redline synthetic heavy shock proof gear oil
Transfer case - Redline synthetic high temp ATF
Power Steering - Redline synthetic PS fluid
Chassis Grease - Mobil synthetic chassis grease
Brake Fluid - Valvoline synthetic DOT 4 brake fluid

Steve

F9K9 · Post by **F9K9** » Thu Oct 12, 2006 8:54 am

Thanks! That's what I meant. I'll go synthetic there next time.

Post by **HenryJ** » Thu Oct 12, 2006 2:27 pm

killian96ss wrote:...Synthetic oils are superior to convention oils in every possible way.

Not quite! ...PRICE

My rig sees way too much dirt and water to afford synthetics as much as I need to change fluids.

killian96ss · Post by **killian96ss** » Fri Oct 13, 2006 11:11 am

HenryJ wrote:
killian96ss wrote:...Synthetic oils are superior to convention oils in every possible way.
Not quite! ...PRICE
My rig sees way too much dirt and water to afford synthetics as much as I need to change fluids.

If you think about it synthetics cab be run 2-3 times longer than conventional oils so there really isn't any price difference.

I would rather pay more up front and get superior protection and longer drain intervals.

Steve

Post by **HenryJ** » Fri Oct 13, 2006 1:53 pm

killian96ss wrote:...If you think about it synthetics cab be run 2-3 times longer than conventional oils so there really isn't any price difference.

Oh, but there is. The oil may not break down, but the contaminants are there and still need to be removed. If you never contaminate it (dirt / water) , you may be able to run it longer.

killian96ss · Post by **killian96ss** » Fri Oct 13, 2006 3:52 pm

HenryJ wrote:
killian96ss wrote:...If you think about it synthetics cab be run 2-3 times longer than conventional oils so there really isn't any price difference.
Oh, but there is. The oil may not break down, but the contaminants are there and still need to be removed. If you never contaminate it (dirt / water) , you may be able to run it longer.

I assume you are referring to engine oil since differential oil does not pick up contaminates like dust and water unless your vent lines are in the wrong place, your filters are missing, or your truck is regularly used as a submarine. Mobil 1 extended performance oil can go 15k miles with only a filter change half way through. Conventional oil can only go 3k miles before needing to be changed. Even though the Mobil 1 oil is $5 a quart, it is actually a lot cheaper than regular oil since you can run it so much longer even in dirty environments.

The key here is filter changes, not oil changes.

Amsoil has a synthetic oil that can go up to 50k miles with only a few filter changes in between!

If you run a good air filter or replace it often then there is no reason why dirt should be getting into your oil.

Synthetic oils are also much better than conventional oils in many ways like better gas mileage, superior anti wear properties, better flow at cold temperature, better high temperature protection, etc, etc. There is nothing wrong with being old school when it comes to automotive fluids even though the proof is there that synthetics are far superior to conventional oil.

Steve

F9K9 · Post by **F9K9** » Tue Oct 17, 2006 5:54 pm

Okay, I got in late Sunday night from a trail ride. Rain set in but, I have noticed a minute amount of leakage around the "drain plug" and the "fill" plug on the Summit cover. If, I had washed off the mud, I would not have noticed it. I snugged them up decently. Do I need to add a thread sealant or just tighten them more?

Post by **HenryJ** » Tue Oct 17, 2006 6:31 pm

f9k9 wrote:...Do I need to add a thread sealant or just tighten them more?

Yes. Always use thread sealant on tapered plugs. Especially those of dissimilar metals. The compound helps to prevent electrolysis as well as leaking.

I use Permatex #2 or NAPA joint sealant with teflon. I don't like the tape.

killian96ss · Post by **killian96ss** » Tue Oct 17, 2006 7:17 pm

This is what I use to seal bolts and plugs!

Summit has it for $7.88

"This teflon based sealer has rust and corrosion inhibitors. In aluminum, steel, stainless steel, and plastic, it delivers a flexible, leakproof seal against coolants, water, gasoline, natural gas, and LPG. This sealer is effective from -30 to 550 degrees F, and has a sealant range of 10,000 psi"

Steve

F9K9 · Post by **F9K9** » Tue Oct 17, 2006 7:26 pm

Thanks Brule and Steve

Guess I know what I'll be doing later this week.