Working under the coach

[Fred Cook]

 I am thinking about changing out my transmission fluid and filters myself.  I also need to change out my transmission cooler.  I am confident that I am able to do this but the problem is, not sure I feel safe underneath with only the air bags raising the coach. My coach like many others do not have jacks that lift off the ground, it is leveled off the chassis. So, how do you guys work under your coach in a safe manner.

[Joel Ashley]

A few years ago I got a (12 ton?) compact hydraulic Jack and some (8 ton?) Jack stands at Sears (Craftsman), with the notion of storing the rig unloaded from its tires.  That plan never materialized, but they take up little room in a bay and could be used in any wheel or chassis repair/access circumstance at home, camp, or roadside.

For your instance Fred, just be sure the jack stands or combination thereof are adequate to that part of the coach you need safe support for, and are thoughtfully placed.

Joel

[Dave Atherton]

Fred, at our point in life talking from experience we seem to over look what may look
easy may not. Working under a motorhome scares myself because what seems like you
may have room and movement to work your in tight area you do not. Thinking safety comes first
What happens if, there are many factors to consider other than job at hand. I would suggest
using wood blocking ( wood blocking against steel less chance to slip veris steel against
steel like jack.) Over years in my working days, have seen several mishaps that were over
looked by not using enough blocking to shore or hold something very heavy like a piece
of heavy equipment or motorhome low to ground. Do not assume that what is holding in
place Motorhome it will not slip out. Dave Atherton Retired Cat Mechanic

[Jerry Emert]

A little off subject...kind of!  I've working myself up to the same type of work as Fred is contemplating.  Oil changes, tranny filter changes, basically LOF type stuff.  Getting under the MH is daunting!  My question, are Harbor freight jacks and jack stands safe enough to use?  A lot less expensive and everybody mentions how cheap they are but everybody seems to have something harbor freight in their box.  Would y'all trust them?  Thanks
Jerry

[Samuel Sperbeck]

Hi Jerry,

I have a Harbor Freight 20 ton air over hydraulic jack and it has worked well. Although I don't use it a lot it sure beats a regular hydraulic jack. I am fortunate to have a 20' pit in my shop so I can safely work anywhere under my Beaver by turning it around. I made spacers from 3" X 5/16" wall mechanical tubing with 1/4" plates welded on both ends and place them between the retracted SMI leveling jack pads and the axle pads. That way I am not depending on the hydraulic leveling jacks or the air bags to keep the body from dropping. If the air bags deflate while working under the coach (coach stays up for days) I use shop air to inflate the air bags to remove my spacers. In your case, where you have to crawl under the coach, your method of using jack stands would be safer.

Good luck and be safe, Sam

[Doug Allman]

Jack stands are only as good as their rating and the firms reliability that can produce a document for the testing by an approved lab. Then it comes to the pin that holds the extended jack riser in place. Its rating is far more critical and I have one that sheared with less than half its ratings weight on. All jack stands went into trash from my shop.

Dave Atherton is very correct in that wood blocking is far more safer and has no chance to let a suspended weight drop or shift. That can easily be achieved by going to a box store and getting a 6x6 post cut into 16" lengths for that blocking needed. You then can build a crib on solid reusable wood with those blocks and work very safely under a vehicle the size of a coach.

[Adam Hicklin]

Where exactly do you use these wood blocks?   Between the body and axels?  Can someone explain the process one would use to properly raise and support the coach?

[Jim Nichols]

Doug and Dave are correct in using wood timbers. I will raise the coach with the HWH air system. Then I measure the frame to the axle by using only my arms and a flashlight. Then cut to my measurement the blocks needed. I don't use metal jack stands just wood. Harbor Freight stands are for cars and pickups. I do have a 20 ton air over hydraulic jack using it one tire at a time and block that distance from ground to axle especially when greasing the axle. I'm not referring to 2x4's more like 4x4's and bigger. We only have one chance at getting it right crawling under there. If you have an incline on your driveway you can lower the front making the rear higher if it's just an engine or transmission oil change. No matter what system your inclined to use block the wheels ALWAYS.         

[Jerry Emert]

 block that distance from ground to axle especially when greasing the axle. I'm not referring to 2x4's more like 4x4's and bigger.     
[/quote]
Jim, having a hard time visualizing this.  I'm picturing a 4X4 standing vertically upright between the ground and the coach.  Doesn't seem safe so I'm sure I'm missing something.

When I tried to have a RV Service Center fix my creeping slide (hydraulic leak,) the tech, not a big guy, couldn't fit under the axle to work on it.  They couldn't figure out how to get under it.  Yes pretty incompetent but that is why I asked about jacks and jack stands.  Several other service centers in Oklahoma and Arkansas refused to even try so I finally gave up and drove home to Florida with the slide blocked.

Probably going to have to build the ramps I've seen described here but they take up a lot of room I just don't have much of.

[Stan Simpson]

There is a body shop in Janesville WI that specializes in body work, alignment, and other work for big tour buses, etc. They also have a certified Aqua Hot tech.

They have a lift that can raise any coach in the air.

I would search for someone like that.

[Mike Shumack]

If your doing the work yourself, there are a couple of ways to support the coach - depending on what your doing.

1) If you need room to get under coach to drain oil for example, you could drive up onto some blocks (stacked blocks tapered like a ramp, but wide and long enough to fully support the tire width contact patch. Like 2"x12"s stacked where the bottom board is 24 inches long, the next board screwed to it is 18", then 14", 10", etc.). You would also cut a 45 on the board edge to make it more ramp like).

2) Jack up the coach (i.e. Hyd. Bottle Jack) under the axles and put jack stands on each side of axle for support (never trust the jack alone). Be sure to chock the front wheels if you lift the rear wheel off the ground.

[Jerry Emert]

If your doing the work yourself, there are a couple of ways to support the coach - depending on what your doing.

1) If you need room to get under coach to drain oil for example, you could drive up onto some blocks (stacked blocks tapered like a ramp, but wide and long enough to fully support the tire width contact patch. Like 2"x12"s stacked where the bottom board is 24 inches long, the next board screwed to it is 18", then 14", 10", etc.). You would also cut a 45 on the board edge to make it more ramp like).

2) Jack up the coach (i.e. Hyd. Bottle Jack) under the axles and put jack stands on each side of axle for support (never trust the jack alone). Be sure to chock the front wheels if you lift the rear wheel off the ground.

Thanks Mike that is what I had see  Thanks
Jerry