Two lift questions.

Do I need to make adjustments to the brake proportioning system when lifting a gen 3 Tundra?

My 97 Tacoma used the old school proportioning valve, hooked to a lever that would move depending on the load in the bed. It too required an adjustment when lifting.

I don’t see this system on the Tundra.


Driveline vibrations when lifting?

My 97 Tacoma required axle shims after lifting 3” in order to re align the driveline angle to stop a nasty vibration.

Can I expect the new Tundra to need the same when lifting by about 2”?

 

There are a few different diff. drop kits for the front end, but you don't need it for only 2 inches. The TRD Pro comes with a 2 inch lift in front compared to all other Tundras, and the control arms and diff setup is the same. I have never heard of anyone having to mess with brakes after lifting, and I don't think these trucks have a proportioning valve that you can adjust anyways. There are also carrier bearing drop kits if you get vibrations from your pinion angle when lifting the rear. I wouldn't worry about that either at 2 inches.

 

You should not need either of those with a 2 inch lift. I did have a slight shutter/vibration at take off with my 3/1.5 lift but the @Coachbuilder1 carrier bearing drop kit fixes that right up.

 

There 100% is a proportioning valve on these trucks. And its position/calibration depending if you lift or level will change. This also composites for loads in the bed and trailer towing.

Will it have a big life changing effect if you don't do a re-calibration I would argue "no." Same with diff drop for a 2" lift.

But, if you have techstream (or the ability to accomplish the sensor recalibration) and want to retain the best angles in the front why won't you drop the diff and driveshaft with a spacer. (granted maybe you're rock crawling and the height on the front diff and transfer case are meaningful to you.

FWIW

 

Thanks for the pic. The visual helps a lot.

Looks pretty simple.

Dang, your truck is so clean. Go get that thing dirty.

 

Thanks for the informative reply.

So the proportioning valve works on bed height and angle of the truck and is calibrated to the stock spring rate? Is it mechanical, like old school, or some sort of modern gizmo that uses different data in order to do its job?

I’ll be going with a spring lift, like Alcal or similar. I think the spring rate will not be the same.

Can this be accounted for when calibrating the proportioning valve?

Asking because although I installed a simple bracket spacer, same height as the lift, on the 97 Taco, the stiffer spring rate fooled the proportioning valve. That is to say, it did not know how heavy the load was. The air bags I used for a short time would also fool the proportioning valve.

Hoping to keep the 2021 Tundra as safe as possible.

Edit:
The truck will never tow or have a heavy load.

Just a 250-pound camper shell and about 600 pounds of camping gear, max.

 

Hate to be the bringer of bad news but unless you have a single cab tundra or drive solo i'm pretty sure your plan will exceed your gross vehicle weight limit for cargo, etc. Tundra's are great at many things but load capacity isn't/ain't one of them. Disclaimer: This from lots of forum reading, lots of guys are way over payload with overlanding gear and only 1 outta 1 million seems to have anything fail.

https://www.tundras.com/threads/max-payload-issue-help.25511/


This gizmo is electronic and has a zero point calibration that can get out of wack if you level or lower your truck. Without that valve you'd never wear out your rear brakes as the weight transfer from the front to rear is 70% typically. But, again I don't work on trucks for my daily job, i don't design truck suspensions and I don't have much off-road experience, just a weekend warrior (who should probably be) but, isn't afraid to wield a wrench.

 

Thanks for the link. It’s an eye opener.

Door sticker says, Max payload, passengers plus cargo is 1,300 pounds, minus 67 yellow sticker. = 1,233 pounds of payload

Just re calculated the actual weight of the typical payload and its close.

2 people = 290 pounds.

Water = 200 pounds

Gear = 250 pounds

Shell = 250 pounds

Bed liner about 50 pounds

……………………………………………………………………….

1,040 pounds

so I only have 193 pounds to spare.

 

And thanks for the zero point calibration pointer.

Looks easy to do and is necessary to do after most any suspension upgrade, alignment etc., even if keeping the stock height. I’m guessing most any shop does this as standard protocol after the work is completed.