Weak Leaf Springs - Help with new setup

I'm in need of replacing both rear leaf assemblies and figured I might as well change out my rear shocks while I'm under there. I have 90K miles on my truck and broke both stock leaf set ups (not surprised given what i've read). I ordered two sets of heavy duty 3/1 leaf setups (as opposed to the stock 2/1) and some Bilstein 5100s.

Two Questions:

1) Can I get away with waiting to replace my front end shocks or should I replace them soon since I am going through the trouble of replacing the rear set up? I was thinking of just getting 5100s on all four corners.

2) Do I need to get an alignment if I'm only doing the rear leaf and shock install?

Thanks in advance for any suggestions and advice. I'm fairly new to the site and still learning how to best navigate for needed info and figure I'd get most out of just posing these two main questions. Any additional thoughts on my proposed set up, curve balls I need to think about, etc., would be helpful. Thanks again!

 

1) Shocks only have to be replaced in pairs, so you'll be fine waiting to do the front's. (As long as there is physically nothing wrong with them.)

2) No alignment required if you don't mess with the front end

 

Excellent. Thanks. Will make a two-phase project then.

 

I'm not sure about that alignment. I know in the TSB for replacing the factory 3 pack leafs with the factory 4 pack they say an alignment on the front is necessary.

From personal experience I know that if they don't align the front after putting in the 4 pack leafs on then the front will be out. Had the TSB done on my truck. They didn't align the front. From the dealership to the interstate was all 25 mph and it wasn't noticeable till I got up to speed, but the front was out. Turned around at the first opportunity and went back to the dealer. Told them they didn't do an alignment like the TSB said. After some conversation and checking the TSB they took it back for an alignment. Didn't get it right and got it aligned at another dealer at the first dealers expense.

 

So that's saying that the new rear leafs change the axle location. Kinda hard to believe, being that it's plug and play parts. But, based on this, I guess the correct thing to do would be to drive it after install, if it tracks weird or has shaking in the steering wheel have it aligned.
Although in my years of working on cars, any work performed on the rear end didn't require an alignment. But that's changing like part for like part, not upgrading.

 

i guess over 90k the taco would have acquired the lean as well as regular sagging....put new, taller leafs in the rear changes the weight ratio front to rear and could potentially minutely change the front specs

 

Thanks for chiming in, folks

I've decided to just replace all 4 corners with Bilstein 5100's and will just get the truck aligned when install is complete.

Looks like the leaf set up that I purchased has the same number of leaves as the factory set. I guess I was misinformed as to what 3/1 vs. 2/1 meant. I'm still very new to this stuff. That said, I'm sure the heavier duty 3/1s with the billies will temporarily add some small amount of rear lift until they break in. Since there is not an extra leaf involved, as I initially thought, I am assuming I should just set my front billies to either 0 or .85?