Questions about welding the axle tubes

[Yama-Bro]

Hi Guys,

I am to the point where I can weld my axle tubes to the center section. I have been planning on doing this for awhile, however I started reading some stuff on the internet and now I have mixed feelings about doing it. I know the advantage of welding the tubes is that they won't rotate under torque. As far as disadvantages that I've been reading: potential to cause the tube to get out of alignment due from the heat, potential for the axles or center section to crack right where the weld is. As I understand it with my limited welding experience, it is difficult to get a strong weld between cast and steel. Today, I took my axle to a local machine shop and they were steering me towards not welding the axles. They said they can do it, but can't guarantee it will help or hold up. The plug welds in my housing still look good. I am planning on having a 400hp engine, although it could potentially be upgraded to 450hp. Is it worth it to weld the tubes? What are your thoughts?

Thanks!

[Packer fan]

I didn’t think the tube was cast. I do not believe it needs to be welded on the other side.
That being said I do think it would be strong enough without being welded because of the notch.

Just my 2 cents worth

[Jeff Kleiner]

IMO, unless you plan to do drag race launches on slicks the "fuse" will be the tires---in other words I do not see much potential for axle housing failure on street tires.

Jeff

[NAZ]

If this is a Ford 8.8 then yes, it is worth it to weld the axle tubes to the cast steel. I did mine but there is a specific process I use to ensure a quality end product. A machine shop or welding shop that is not familiar with the correct process will likely not provide you with good results. You need a fixture to prevent the axle tubes from warping from the heat. It requires 99% Ni rod and to use a procedure that minimizes the heat affected area and stress relief of the weld between passes while the weld is cooling. If you rush the job or use the wrong material or no fixture you will likely not be happy with the results. If you hear that dreaded "tink" when welding or while it's cooling you will have to grind out the weld and start over as you just created a crack from rushing the work or using the wrong filler.

[DadofThree]

I welded mine. Mine was a donor that had grease coming through the joint. After welding I then had to grind away some of the weld to get the banana bracket to fall in place. I just took my time and tried to keep down the heat while doing opposite sides of the tube to minimize deflection. I did it because I had grease coming through the joint. Otherwise, I wouldn't have touched it.

8.8 Rear Album (https://www.flickr.com/photos/annabellerose/albums/72157681393322662)

https://farm5.staticflickr.com/4225/34755604401_7d04814123_c.jpg (https://flic.kr/p/UXeyjD)IMG_2167 - Copy (https://flic.kr/p/UXeyjD) by D. R. (https://www.flickr.com/photos/annabellerose/), on Flickr

https://farm5.staticflickr.com/4219/34500601450_8a8bf30b2d_c.jpg (https://flic.kr/p/UyGAQ3)IMG_2227 (https://flic.kr/p/UyGAQ3) by D. R. (https://www.flickr.com/photos/annabellerose/), on Flickr

[rich grsc]

IMO, unless you plan to do drag race launches on slicks the "fuse" will be the tires---in other words I do not see much potential for axle housing failure on street tires.

Jeff
Going to agree, a waste unless you're building a hardcore drag car. This is the axle used in millions of 3600# or heavier Mustangs, you don't hear of Ford having any come back problems with them. These cars are over a 1000# lighter, going to take some serious power and tires to cause a problem.

[Sdtoothdoc1]

I have a Moser 8.8 that I had to get narrowed by 1" on each side to get the FFR halibrand style 18" rims/tires to tuck under correctly(different offset/backspacing than the 17" with the same size tires). It should have been an easy job..took out the axle and had a local shop do it on their jig. New custom axles were put in. Well, something must have happened during the process(dropped?), because I had a gear fluid leak from my passenger side where the tube meets the center section area. It was pain to weld...getting a clean weld since there is fluid on the inside contaminating the weld. Even with it drained, couldn't get a good weld. Had to put a torch on the area to be welded to burn off the residual fluid, then weld. So far, no leaks but this is the spot where it was leaking from.

For those saying not to weld, what is the other option to seal so fluid won't leak between the junction of the axle tubes and housing?

[DaveS53]

If I was building one of these cars, I'd get a 9 inch Ford rear end to start with. Then you'd have welded tube and no iron center. You can buy them made to fit the donor cars that the 8.8 rear ends come from. Then add some Wilwood brakes.

[Yama-Bro]

If I was building one of these cars, I'd get a 9 inch Ford rear end to start with. Then you'd have welded tube and no iron center. You can buy them made to fit the donor cars that the 8.8 rear ends come from. Then add some Wilwood brakes.

That's a thought, but it seems much more complicated and expensive. If going that route, it may be cheaper and easier just to get the IRS in the first place.


Going to agree, a waste unless you're building a hardcore drag car. This is the axle used in millions of 3600# or heavier Mustangs, you don't hear of Ford having any come back problems with them. These cars are over a 1000# lighter, going to take some serious power and tires to cause a problem.

This is something I was kicking around in the back of my mind to. Wasn't this axle also used in Ford trucks and explorers?

[Yama-Bro]

Thanks for the comments and advice guys. I'm really leaning towards not welding them now. I don't have any leaking issues (that I can tell) and the current plug welds look really good. I have no plans of running drag radials, and may only go down the drag strip a few times. And bonus of not doing it is that my banana bracket will still fit without grinding (not that that's a big deal). And then to top it off, it sounds like if I want to do it right, I'm going to need to find someone that knows what they are doing. The local welders I talked to yesterday have a lot of experience, but I don't think they've dealt with one of these axles before...so they probably aren't the guys I should choose, if I were to do it.

If anyone else has anymore advice, keep it coming. I'll take anything into consideration.

[DaveS53]

Nothing complicated about using a 9 inch, but it's not cheap. The kit comes with everything you need, except the differential, but that can run $1200-1600, with a good posi unit.

https://www.speedwaymotors.com/Speedway-Ford-9-Inch-Bolt-In-Rear-End-Axle-for-1979-93-Mustang,291310.html

https://www.summitracing.com/search?SortBy=BestKeywordMatch&SortOrder=Ascending&keyword=9%20inch%20ford%20center%20section

[Gromit]

I would suggest a little more research. I think someone makes a bracket that goes between the banana bracket and the original upper center 4 Link that may be a good compromise Its a minor concern of mine that the torque load in the stock 4 link setup used the pumpkin and both axle tubes and now its all taken up on just the axle tube on one side. I know someone over in the 33 side had the used 8.8 the plug weld failed and the tube did twist. I would think about the what is the worst that can happen and work to minimize that possibility.

https://thefactoryfiveforum.com/showthread.php?25171-3-Link-support-Is-it-needed

Just my $.02
Chris AKA Gromit

[Yama-Bro]

I would suggest a little more research. I think someone makes a bracket that goes between the banana bracket and the original upper center 4 Link that may be a good compromise Its a minor concern of mine that the torque load in the stock 4 link setup used the pumpkin and both axle tubes and now its all taken up on just the axle tube on one side. I know someone over in the 33 side had the used 8.8 the plug weld failed and the tube did twist. I would think about the what is the worst that can happen and work to minimize that possibility.

https://thefactoryfiveforum.com/showthread.php?25171-3-Link-support-Is-it-needed

Just my $.02
Chris AKA Gromit

Thanks Chris... I did just order the VPM 3 link brace about 2 hours ago. So I have that part taken care of.

http://www.vintageperformancemotorcars.com/

[cgundermann]

Thanks Chris... I did just order the VPM 3 link brace about 2 hours ago. So I have that part taken care of.

http://www.vintageperformancemotorcars.com/

Very, very nice high quality part; fits & works perfectly.

Chris