lube for 7.5" ford rearend

[steamer]

For all you folks with the ford rearend. How full is full as far as how much lube to put in? Motortrike manual says 3.3 pts,and also says to within 1/4 to 3/8 inch of fill hole??? 3.3 pts doesn't come close to the fill hole. Acually 2 qts doesn't come close to the fill hole. So what is the right answer?

 

[Nana]

Perhaps the Motortrike service manual will help. There is a PDF Motortrike service manual in this this link. Perhaps it will give you the answers you need: <a href="http://www.triketalk.com/forum/honda-trikes/315-motor-trike-service-manual-finished.html" target="_blank">http://www.triketalk.com/forum/honda...-finished.html</a>

 

[steamer]

Thanks Nana, but thats where I got the info I was asking about in my post. The manual has conflicting info. I was just woundering what others here are doing.

 

[Ol' Grey]

Same confusion with the Suzuki/Lehman trike I've been working on. Ford (of some sort) rear differential. The Lehman online pdf. manual doesn't offer any capacity spec, just says to "check rear differential fluid regularly". After 9 yrs. without any real servicing (yes, maintenance was embarrassingly neglected) decided I'd better check it. <br />
<br />
Removed the level plug and added hypoid fluid until it j-u-s-t started dripping out of the level plug hole........it took 2.8 QTS.!!! YIKES!!! Owner said it rides much better now (there's a big surprise, LOL! Lucky the rear-end didn't go south)<br />
<br />
Venturing a guess here.......is it possible that the Motortrike spec is a misprint ?

Instead of 3.3 pts., could they mean 3.3 QTS. ?

 

[steamer]

<div class="bbcode_container">
<div class="bbcode_quote">
<div class="quote_container">
<div class="bbcode_quote_container"></div>

<div class="bbcode_postedby">
<img src="images/misc/quote_icon.png" alt="Quote" /> Originally Posted by <strong>Ol' Grey</strong>
<a href="showthread.php?p=76751#post76751" rel="nofollow"><img class="inlineimg" src="images/buttons/viewpost-right.png" alt="View Post" /></a>
</div>
<div class="message">Same confusion with the Suzuki/Lehman trike I've been working on. Ford (of some sort) rear differential. The Lehman online pdf. manual doesn't offer any capacity spec, just says to "check rear differential fluid regularly". After 9 yrs. without any real servicing (yes, maintenance was embarrassingly neglected) decided I'd better check it. <br />
<br />
Removed the level plug and added hypoid fluid until it j-u-s-t started dripping out of the level plug hole........it took 2.8 QTS.!!! YIKES!!! Owner said it rides much better now (there's a big surprise, LOL! Lucky the rear-end didn't go south)<br />
<br />
Venturing a guess here.......is it possible that the Motortrike spec is a misprint ?

Instead of 3.3 pts., could they mean 3.3 QTS. ?</div>

</div>
</div>
</div>I was thinking the same thing. I remember back in the good old days when all cars were rear wheel drive,anytime we added lube to the rear ends,you allways filled it to the fill hole.

 

[kj5ix]

Yep it is a typo,,, <img src="images/smilies/redface.gif" border="0" alt="" title="Blush" class="inlineimg" /><br />
<br />
Fill it up to just before it runs out. Now just like mentioned above just a trickle would be good. In the old days when checking the rear end I put my pinky in the hole, and crooked it down, and if it got lube on it it was good to go. Any where in that area will be good.<br />
<br />
I guess I will have to change the typo some day.....

 

[steamer]

Thanks for the info. I'm sure glad I didn't put many miles on it since the lube change. Going to top it off today.

 

[Matches]

Roadsmith cautions against filling until the oil runs out. Their spec is add 1 qt after draining.<img src="images/smilies/shrug.gif" border="0" alt="" title="Shrug" class="inlineimg" />

 

[steamer]

<div class="bbcode_container">
<div class="bbcode_quote">
<div class="quote_container">
<div class="bbcode_quote_container"></div>

<div class="bbcode_postedby">
<img src="images/misc/quote_icon.png" alt="Quote" /> Originally Posted by <strong>Matches</strong>
<a href="showthread.php?p=77057#post77057" rel="nofollow"><img class="inlineimg" src="images/buttons/viewpost-right.png" alt="View Post" /></a>
</div>
<div class="message">Roadsmith cautions against filling until the oil runs out. Their spec is add 1 qt after draining.<img src="images/smilies/shrug.gif" border="0" alt="" title="Shrug" class="inlineimg" /></div>

</div>
</div>
</div>ONE Quart are they nuts. i have 3 qts in mine and it still isn't all the way to the fill hole. It's about 3/4" below and thats where is going to stay. At one qt. theres not enough in the rear end to run down the axcel casing to lube the wheel bearings. unless your rear end is mounted upside down,then maybe one qt would work. Not sure about that.

 

[Ol' Grey]

Not sure if Roadsmith uses the same rear differential on all of their trikes, but did a quick search for "Roadsmith rear end" and it said that they use Dana 30 Spider gears in the housing. Then did a search for "Dana 30 rear differential fluid", which took me took a Jeep forum. Apparently on some Jeeps, it's a Dana 30 for the front differential, Dana 44 for the rear differential. I can only guess that Roadsmith is using a Jeep front differential (Dana 30)........anyways, in the discussion on the Jeep forum, it said that the fluid capacity for the D30 was 1-1.2 qts. and on the D44 it was 1.6 qts.

Heck, I'm still trying to figure out what Ford rear end is on this Lehman, LOL! All I'm sure of is that this one took 2.8 qts. and I've got no idea what little was in there to begin with. Sticking with the level plug here as well.

There was some mention on the Jeep forum about a filler plug on the differential housing cover.

Guess some aftermarket covers have the fill plug up higher, so one wants to only add the recommended amount for those so's not to overfill the Dana's.........

Spoke with an auto mechanic bud again about this Lehman and he said to bring it over to his place and he'll see if he can identify which Ford model the rear end is from. When I told him it took 2.8 qts., he said the owner was very lucky that the rear end hadn't blown out. Am also remembering when I first starting researching this stuff, one article said that these Ford rear ends are pretty substantial........."Built Ford Tough" applies in this case as it held up with a fluid capacity that was obviously way below spec.

 

[Matches]

They don't use the same rearend on all of their trikes. I was quoting what they rec. for the Ford. The Ford is used in the HT1800 and some others. The Dana is used in the VTX conversions. Roadsmith does not use a wet axle in the kit.

Shaft Driven Differentialford differential

Our differential is constructed from standard automotive ring and pinion gear sets. The original application of our differential was a Ford car. We cut down this brand new cast iron housing and make an Independent Suspension differential out of it. The components inside it are all brand new including the 2.93:1 ratio ring and pinion. We keep the speedometer correct with that ratio and tire diameter.

 

[Lehman Trikes]

Ol' Grey,
I can't speak to what any of the other trike manufacturers use but the Suzuki C50 and C90 conversion by Lehman Trikes use a diff based on the Ford 6.75" design. We also run that diff upside-down from how it would have been installed in a car. The early units used the original cover which means that if you fill to the drain plug it is WAY over full. We call for 30 oz of 80-90 gear lube for that application.

 

[Ol' Grey]

They don't use the same rearend on all of their trikes. I was quoting what they rec. for the Ford. The Ford is used in the HT1800 and some others. The Dana is used in the VTX conversions. Roadsmith does not use a wet axle in the kit.

Shaft Driven Differentialford differential

Our differential is constructed from standard automotive ring and pinion gear sets. The original application of our differential was a Ford car. We cut down this brand new cast iron housing and make an Independent Suspension differential out of it. The components inside it are all brand new including the 2.93:1 ratio ring and pinion. We keep the speedometer correct with that ratio and tire diameter.

The more I read and research, the more I discover things that I don't know about :AGGHH:........My preference is wrenchin' on bikes and this is only the first (and probably last, LOL!) trike that I'm trying to maintain for a friend.

When you say that Roadsmith does not use a wet axle in the kit, does this mean that there's "wet" axles and "dry" axles ?

You quoted a fluid capacity spec of 1 qt. for the Ford differential used by Roadsmith. Does this mean that they've isolated the ring and pinion gears in the differential housing and that the 1 qt. stays contained in the housing ONLY ?

 

[Ol' Grey]

Ol' Grey,
I can't speak to what any of the other trike manufacturers use but the Suzuki C50 and C90 conversion by Lehman Trikes use a diff based on the Ford 6.75" design. We also run that diff upside-down from how it would have been installed in a car. The early units used the original cover which means that if you fill to the drain plug it is WAY over full. We call for 30 oz of 80-90 gear lube for that application.

Thanx very much for offering this, Lehman. Yes, I've pretty much figured out that the differential on this trike (2002 Suzuki VS800/Lehman) is from a Ford 6.75". There's a vent on the topside of the differential housing and the housing cover has no fill plug, only the 8 cover mounting bolts. The level plug (or at least what I'm thinking is the level plug and not an upside down drain plug) is situated on the inner, upper left side of the housing (opposite side from the cover side).

Am I correct in thinking that this differential has been installed right side up as it would have been in a car ? If it's been installed upside down, then the vent that is currently on "top", would have been venting DOWN in an auto application...........and, IF this differential is installed right side up, would the hypoid fluid capacity be more like 3 qts. rather than the 30 oz. that you've just mentioned ?

 

[Lehman Trikes]

Ol' Grey,
The diff you are working with is most certainly one of the early ones. The plug you are referring to would have been the level/fill plug in an automobile application. The diff is installed upside-down and the vent was moved to accomodate the change in orientation. 30 oz of gear lube is all it should need.

 

[Ol' Grey]

Ol' Grey,
The diff you are working with is most certainly one of the early ones. The plug you are referring to would have been the level/fill plug in an automobile application. The diff is installed upside-down and the vent was moved to accomodate the change in orientation. 30 oz of gear lube is all it should need.

Thanx once again, Lehman, but ut-oh.....now it's overfull.......:gah:

Spoke with my auto mechanic bud and he concurred that if the differential had been installed upside down, either for more clearance or due to the need for the drive shaft to work in the proper direction, then yes, the fluid capacity would be much less as you've noted. Told me a quick way to check whether it was upside down or right side up was to look at the pumpkin. If the bulbous portion of the pumpkin was on top and the receiver for the drive shaft on a car was located near the bottom, then it was right side up. If it was opposite of that, then it would have been installed upside down. Will check that just to check it, but am assuming by what you've just said, I'll be draining a couple qts. of fluid out.

Hope that "steamer" is reading this in case his Motortrike rear end has also been installed upside down, which would mean that he also did an overfill, same as me. Will also PM him to give him a head's up.

Thanx again, Lehman and Ride Safe.........

 

[Ol' Grey]

Just eye-balled it and sure enough, it's been flipped, so will have to drain the excess.

Matches........Am guessing that Roadsmith also installs their Ford rear ends upside down as well, which means that you were correct on the 1 qt. capacity.

Just what I needed........more work! LOL! :woohoo:

 

[Papa Zook]

Thanks Clay @ Lehman for watching and answering questions...It gets no better than coming straight from the manufacturer!

 

[Ol' Grey]

I'll second that, Bazooka.........won't deny that there's been some frustrating times trying to figure some of this stuff out, but Clay@Lehman came thru yesterday in a big way! :wtg:

Still have to drain this excess fluid from the differential. Ideally, I should remove the housing cover, let the fluid drain, then add the recommended amount. Two questions on this:

Is the housing cover gasket a Fel-Pro RDS13073 ?
Anyone know the torque spec for the 8 housing cover bolts ?

If I wanted to do a temporary drain this time until I can get the right gasket, would removing one of the lower cover bolts work as far as draining the excess ? Meaning, if a lower cover bolt was removed, would the fluid drain thru there or does the bolt go into a closed, threaded casing ?

 

[Papa Zook]

Hope Clay doesn't mind me sharing this, he and his family have been involved in Lehman since 1993. Clay's dad Larry Strilchuk became John Lehman's partner and then Lehman Industries became Lehman Trikes in 1993. Larry went on to become president and CEO of Lehman Trikes. Clay had never mention this fact, but I now know that Clay KNOWS Lehman Trikes and we are fortunate to have his personal input here.

 

[Ol' Grey]

Been thinking about the confusion that resulted in an overfill of the differential. When I gave it a quick look the other day, noticed some fluid seeping thru the "level" plug but nothing coming out of the vent. Once I drain and add the correct amount, am HOPING that this will set it to rights since the owner probably put less than 200 miles on the trike since the overfill. (Not sure if Motortrike installs their Ford rear ends upside down or not, and can only hope that "steamer" is good to go since he basically added the same amount to his trike that I did to this one). Someone here off-line came up with an excellent suggestion that I'll pass along FWIW.......if the manufacturer installs the rear end upside down, which changes the required fluid capacity, it would be helpful if the manufacturer would STAMP THE NEW CAPACITY SPEC SOMEWHERE NEAR THE FILLER HOLE (caps for emphasis, not yelling).

Still have to drain this excess fluid from the differential. Ideally, I should remove the housing cover, let the fluid drain, then add the recommended amount. Two questions on this:

Is the housing cover gasket a Fel-Pro RDS13073 ?
Anyone know the torque spec for the 8 housing cover bolts ?

 

[Matches]

OL' Grey,

Yes the Roadsmith is isolated and the fluid is contained in the rear end. Its an independent rear suspension so you esentially have two half shafts bolted onto a sealed rear end going out to the wheel and bearing assembly.

 

[Lehman Trikes]

If the cover is an octagon shape then the gasket p/n you have is correct. It is an older square cover then the gasket p/n is RDS55323. Torque the housing cover bolts to 18 ft.lbs.

 

[Ol' Grey]

OL' Grey,

Yes the Roadsmith is isolated and the fluid is contained in the rear end. Its an independent rear suspension so you esentially have two half shafts bolted onto a sealed rear end going out to the wheel and bearing assembly.

Thanx for the clarification, Matches.....Pretty sure I'm following now what you said earlier about Roadsmith not using a wet axle in the kit. Am picturing the fluid in the housing but no fluid in the half shafts.

Since the subject has come up, do you know if Roadsmith installs their Ford rear ends upside down as well ? Still not sure if Motortrike does or not and am wondering if this is a common way (or the only way ?) of installing automotive rear ends on trikes and, if so, why ?

Thanx again and Ride Safe ThumbUp

 

[Ol' Grey]

If the cover is an octagon shape then the gasket p/n you have is correct. It is an older square cover then the gasket p/n is RDS55323. Torque the housing cover bolts to 18 ft.lbs.

Much appreciated, Clay ThumbUp.........Yes, it's the octagon shaped cover. Also, when I gave it a quick look the other day, noticed some bosses on the housing that I hadn't seen before. They may or may not have letters or numbers on them, but when I get time to drain the excess fluid, will see if I can read anything on those bosses and see if it helps narrow down what Ford this rear end is from or not.....hehehe.........

Have a GREAT weekend and Ride Safe...........

 

[steamer]

Well guys I'm here to tell you,in accordance with Motortrike manual for there 7 1/2" ford rear end. Which kj5ix was kind enough to up load for us. It states " fill the rear differential to with in 1/4" to 9/16" of the fill hole" in the next line it states " it should take 3.3 pts of lube " just one problem with this, I filled mine to with in 1/2" of the fill hole. It took 3 QTS of lube????? I went on a 400 mile run last week and all is good. I would also have to say that if I were to but 3.3 pts in the diff. I don't believe the axcel bearings would get enough oil.

 

[Nana]

Well guys I'm here to tell you,in accordance with Motortrike manual for there 7 1/2" ford rear end. Which kj5ix was kind enough to up load for us. It states " fill the rear differential to with in 1/4" to 9/16" of the fill hole" in the next line it states " it should take 3.3 pts of lube " just one problem with this, I filled mine to with in 1/2" of the fill hole. It took 3 QTS of lube????? I went on a 400 mile run last week and all is good. I would also have to say that if I were to but 3.3 pts in the diff. I don't believe the axcel bearings would get enough oil.

Steamer, go back to page one of this same thread. kj5ix posted that he had made a typo in the manual and explains what the correct amount of oil is.

 

[steamer]

Steamer, go back to page one of this same thread. kj5ix posted that he had made a typo in the manual and explains what the correct amount of oil is.

Thanks Nana, I did read his reply. I agree with kj5ix, but several people here seem to be confused about this. I believe some here are trying to compare the older ford 7.5 inch rear used on older motor tikes with other brands of rear ends use in other brand conversions. I asked the question about the discrepancy in the motor tike manual. Other brands that use the ford rear end may be different, but keep in mind, if it uses a solid axle the wheel bearings use the same lube,so the lube needs to be at the proper level to insure they are lubed. If you look at the fill plug you will see that it is in line with the axle housing. So by filling to the bottom of the fill hole you are insuring you will have lube to the bearings. It doesn't matter if the pumkin is upside down or right side up. As long as you fill to the bottom of the hole you will have lube to the bearings

 

[Ol' Grey]

The controversy rages on.......LOL! All in good fun, no argument or ill feelings here as we try to sort the various designs out.

Found some good pics of the Roadsmith Ford rear end that Matches has described. Installed right side up, which answers one of my questions. Please see pics here:

Trikes: HT1800 : Roadsmith Trikes

Will add more tomorrow as I'm a bit road worn here........need to get some zzzzzzz's...........

 

[steamer]

Keep in mind,the roadsmith is independent suspension. It doesn't have wheel bearings out by the wheels. on the solid axle like my motor trike you need to make sure there is enough lube in the axle tubes to lube those bearings. By the way the motor trike rear end is mounted upside down. If you use the motor trike manual that is posted here,keep in mind that all the pictures of rearend and axle assembly is of a full size car rear end,right side up. It is not the cut down,modified rear that is in the trike.