how to positively ID a LDS in a 2-1/2 and Air Filter Options

[quadfourgtz]

I bought a 1971 M35A2 a few months ago. It's suppose to have the LDS engine. There is a plate on the dash that shows it to be an LDS. However, is there some place on the block/engine to positively ID it as a LDS? Additionally, assuming it is, would it be worth/can you put the 5 ton filter setup on the M35A2? TIA

Dan

 

[doghead]

I've never seen a data plate on the dash, that designates the engine model(LDS or LDT). There should be a data plate on the side of the engine block, under the manifolds, and above the alternator.

What do you mean by 5 ton filter setup? An LDS and LDT both use the same fuel and oil filters.

 

[quadfourgtz]

Doghead,

I will check the locations you've mentioned. I'm probably thinking back to a picture from the ad and not sure that I saw it on the dash.

I'm only referring to the air filter/air intake when I say "5 ton filter setup".

 

[jollyroger]

Doghead,

I will check the locations you've mentioned. I'm probably thinking back to a picture from the ad and not sure that I saw it on the dash.

I'm only referring to the air filter/air intake when I say "5 ton filter setup".

The data plate for the engine should be on the passenger side of the engine. It is down from the manifolds and above the generator like doghead said toward the front of the block. It is quite visible. It will have all the engine data on it that disinguishes what type of motor it is.

If I understand correctly, I could be wrong, the fender mounted 5 ton canister air filter is for the 250 Cummins engine on the 800 series trucks. The LDS and LDT engines should share the same Air filter setup.

 

[rat4spd]

Also, there should be a data plate on the injection pump, on the bottom part somewhere that identifies it as an LDS.

 

[doghead]

My experience shows, you do not need a 5 ton air filter setup with an LDS in a 2.5 ton truck.

 

[quadfourgtz]

As I understand it, the LDS requires better air flow than the LDT. If they both have the same airbox, then is there a different air filter for the LDS? TIA

 

[doghead]

The LDS was not designed to be used with the 2.5 ton air filter. Iirc, the LDT filter is rated at 450 cfm. I'd bet the 5 ton filter is rated higher than that.


It will do just fine though. Ask the others here with LDS's in their M35a2's.(with stock filter housings)

 

[rat4spd]

I have never driven an LDT to compare my LDS to, but I will say that the LDS in my truck seems to run pretty darn good with the stock filter.

 

[pittdog]

The plate is on the pass side.. on the engine to the top !

 

[clinto]

LDT = 410 cfm.

 

[doghead]

Indeed, the filter is rated at 410 cfm(I just checked one!)

 

[Recovry4x4]

Clarification on filter housings. Deuce is under the hood as most of us know. The 5 ton multifuel (LDS) has a passenger fender mounted air cleaner whereas the 809 series is on the drivers fender. The 809 series canister is considerably larger in diameter than the multifuel one. I'm afraid the data plate is the only telltale clue unless you take the engine down. Multiple LDS accessories (IP, turbo, compressor intake) all indicate towards and LDS but these parts can be found on LDTs as well.

 

[54reo]

The 5 ton multifuel (LDS) has a passenger fender mounted air cleaner whereas the 800 series is on the passenger fender.

I'm sure Kenny meant "M809 series air cleaner is Driver's side mounted".

 

[Recovry4x4]

You are correct Brian, Thanks!

 

[sandcobra164]

The LDS has a small canister underneath the turbo to actuate the waste gate. The air filter will still be under the hood in the deuce. I've only driven 1 deuce with an LDS and you'll know it has one because it will pull like there's no tomorrow in any gear. My local guard unit has one and when the mechanics first told me it had a 5 ton motor in it, I questioned them saying a NHC 250 wouldn't fit in the sheet metal. They then told me about the LDS and it's a beast in a Deuce!!!!!! I know there are probably other difference's but I'm going to try and at least get the turbo off of that truck and swap my "D" and see if my motor like's the extra air before the truck goes to auction. If not, I'll just add another truck to my fleet until I get what I want. See ya'll at Warner Robins on that auction. All I will say is it's tan and ugly but dang it runs strong.

 

[Flyingvan911]

My deuce sitting at Fort Riley has an LDS. I can't wait to drive it. The general consensus is that the LDS has more pep than the LDT. I wonder if you could put the 5 ton style air filter/housing in the pass side deuce fender? No real reason, just curious.

 

[snakehunter1964]

The starter on an LDS is on the drivers side. That's the quick way to tell it has (or should have, no other reason to put it on the drivers side" the wastegated turbo. The starter won't clear the wastegate if it's an LDS turbo.

 

[NDT]

You will know if you have a LDS if you can stay even with a stock Powerstroke manual transmission up to 55 mph . . . None of that annoying "whistler" racket . . . the turbocharger emits a scream like a jet engine at full thrust.

 

[hemichallenger]

I have a lds in a deuce. No waste gate, starter is on the passenger side. Deuce air cleaner and it runs good.